Eight persons — A, B, C, D, E, F, G and H were studying about different birds in different months of the same year, viz. January, March, May, June, July, October, November and December, but not necessarily in the same order. Each of them is studying about different birds — Kingfisher, Toucans, Penguin, Ostrich, Woodpecker, Loon, Sparrow and Peacock.

G is studying in the month having odd number of days. Either two persons were studying before G or after G. Two persons were studying between G and the one who is studying about loon. H was studying three persons after the person who is studying about ostrich and four months before A. Three persons were studying between A and the one who is studying about Woodpecker. B is studying about Sparrow two persons before F. F is studying before E. The one who is studying about Penguin is studying immediately after the one studying about Kingfisher. Two persons were studying between the ones studying about Kingfisher and Peacock. D is not the first one to study.

Which among the following combination is correct?

To determine the correct combination, we can reconstruct the schedule step-by-step based on the given clues.

First, let's list the months and the number of days in each:
1. January (31 days)
2. March (31 days)
3. May (31 days)
4. June (30 days)
5. July (31 days)
6. October (31 days)
7. November (30 days)
8. December (31 days)

Step 1: Determine the position of G and the Loon.
- "G is studying in the month having odd number of days." (January, March, May, July, October, December have 31 days).
- "Either two persons were studying before G or after G." This means G is either the 3rd person (May) or the 6th person (October).
- "Two persons were studying between G and the one who is studying about loon."
Let's test both cases for G:
Case 1: G is in May (3rd). The loon must be in January (1st) or October (6th).
Case 2: G is in October (6th). The loon must be in May (3rd) or December (8th).

Step 2: Use the clue about H, Ostrich, and A.
- "H was studying three persons after the person who is studying about ostrich" (meaning: Ostrich, [space], [space], H).
- "and four months before A."
Let's analyze the "four months before A" part. The difference in months (not number of persons) between H and A is 4 months. Looking at the list of months:
- Jan (1) to May (5) is 4 months.
- March (3) to July (7) is 4 months.
- June (6) to October (10) is 4 months.
- July (7) to November (11) is 4 months.
Since H is 4 months before A, possible (H, A) pairs are:
- H in Jan (1st person), A in May (3rd person)
- H in Mar (2nd person), A in July (5th person)
- H in June (4th person), A in Oct (6th person)
- H in July (5th person), A in Nov (7th person)

Let's also use: "Three persons were studying between A and the one who is studying about Woodpecker."
Let's test the (H, A) pairs:
- If H is Jan (1st) and A is May (3rd): Woodpecker must be 3 persons away from A (3rd), which means it would be in November (7th). H is in Jan, but H must be 3 persons after Ostrich, which is impossible since H is 1st.
- If H is Mar (2nd) and A is July (5th): Woodpecker must be in January (1st) or December (8th). Since H is in Mar (2nd), and H is 3 persons after Ostrich, Ostrich would have to be 3 positions before Mar, which is impossible.
- If H is June (4th) and A is Oct (6th): Woodpecker must be in March (2nd). Since H is in June (4th) and is 3 persons after Ostrich, Ostrich must be in January (1st). This works!
Let's verify this configuration (H in June, A in Oct, Ostrich in Jan, Woodpecker in Mar):
1. Jan - Ostrich
2. Mar - Woodpecker
3. May - G (since G must be 3rd or 6th, and A is 6th in Oct, so G must be 3rd)
4. June - H
5. July - [Loon] (since G is 3rd, Loon must be 2 persons away, which can be 6th (Oct/A) or 1st (Jan/Ostrich). But Jan has Ostrich and Oct has A. Let's re-read: "Two persons were studying between G and the one who is studying about loon." If G is 3rd, the one studying about loon is either 6th (Oct) or 1st (Jan). But 1st is Ostrich and 6th is A (we can assign Loon to A). Let's see if this fits.)
Let's check the other H and A pair:
- If H is July (5th) and A is Nov (7th): Ostrich must be in March (2nd). Woodpecker must be in May (3rd). G must be in Oct (6th) (since 3rd is occupied by Woodpecker). If G is 6th, Loon must be in May (3rd, but it has Woodpecker) or Dec (8th). So Loon would be in Dec (8th).
Let's check this configuration:
1. Jan - ?
2. Mar - Ostrich
3. May - Woodpecker
4. June - ?
5. July - H
6. Oct - G
7. Nov - A
8. Dec - Loon

Step 3: Analyze the rest of the variables.
- "B is studying about Sparrow two persons before F." (meaning: B [Sparrow], [space], F).
- "F is studying before E."
- "D is not the first one to study."
Let's check the second configuration (Ostrich in Mar, Woodpecker in May, H in July, G in Oct, A in Nov, Loon in Dec):
Positions left for B and F: B is studying Sparrow, two persons before F. Since we have empty positions at 1 (Jan), 4 (June). If B is in Jan (1st), then F is in May (3rd, occupied by Woodpecker) or June (4th, which is 3 positions after 1st? No, two persons before F means B is 1st, then 2nd is empty, 3rd is F. So B is at position n, F is at position n+2).
In our second configuration, the available positions are 1, 4, 8 (but 8 has Loon). So we cannot place B and F such that F is 2 positions after B. Thus, this configuration is invalid.

Let's return to the first configuration where H is June (4th), A is Oct (6th), Ostrich is Jan (1st), Woodpecker is Mar (2nd), and G is May (3rd).
Since G is 3rd, Loon must be 6th (Oct, which is A) because Jan (1st) is already Ostrich.
Let's write down what we have so far:
1. Jan - Ostrich - ?
2. Mar - Woodpecker - ?
3. May - ? - G
4. June - ? - H
5. July - ? - ?
6. Oct - Loon - A
7. Nov - ? - ?
8. Dec - ? - ?

We need to place B (Sparrow) and F (B is 2 persons before F, i.e., B at n, F at n+2).
Available positions for persons: 5 (July), 7 (Nov), 8 (Dec).
Also we have empty person slots at 1 (Jan) and 2 (Mar).
If B is in July (5th), F must be in Nov (7th). This works! B studies Sparrow.
So:
5. July - Sparrow - B
7. Nov - ? - F
Since "F is studying before E", and F is 7th, E must be 8th (Dec).
8. Dec - ? - E
We have person D left, and the remaining position is Jan (1st). But the clue says: "D is not the first one to study."
So B cannot be in July.
What if B is in May (3rd)? But G is in May. B is a person, so B cannot be in May.
What if B is in June (4th)? But H is in June.
What if B is in Jan (1st) and F is in May (3rd)? G is in May, so F cannot be G? F is a person, so F cannot be G.
What if B is in Mar (2nd)? F would be in June (4th), but H is in June.
This means our placement of G at 3rd (May) has a conflict. Let's re-evaluate the positions.

Let's check if H is June and A is Oct, but G is Oct? No, A is Oct. G is 3rd or 6th. Since A is Oct (6th), G must be May (3rd).
Wait, let's re-read: "H was studying three persons after the person who is studying about ostrich"
This means: Ostrich is at position P, H is at position P+3. (i.e. three persons after, so if Ostrich is 1st, H is 4th). This matches Ostrich (Jan, 1st) and H (June, 4th).
"and four months before A."
Wait, four months before A. If H is in June, then A must be in October (June is 6, October is 10, difference is 4 months). This matches.
Is there another combination for H and A?
What if H is in March (31 days) and A is in July (31 days)?
Then Ostrich is in January (not possible since H is 2nd person, Ostrich would have to be -1st).
What if H is in July (5th person) and A is in November (7th person)?
Then Ostrich is in June (4th person, since H is 5th, Ostrich is 5-3 = 2nd person? No, three persons after means Ostrich is at 5-3 = 2nd person, which is March. Yes, March is Ostrich, H is July).
Wait! Let's check this again: H is July (5th person). Ostrich is 3 persons before H, so Ostrich is 2nd person (March). This is what we wrote earlier.
Let's see if we can place B and F in this case: B is 2 persons before F (B at n, F at n+2).
Available persons: 1 (Jan), 3 (May), 4 (June), 8 (Dec) are empty. A is in Nov (7th), G is in Oct (6th), H is in July (5th).
If B is in Jan (1st), F is in May (3rd). Since F is 3rd and studies before E, E can be 4th (June) or 8th (Dec). This works!
Let's fill this in:
1. Jan - Sparrow - B
2. Mar - Ostrich - ? (D or C)
3. May - ? - F
4. June - ? - E (since F is before E)
5. July - ? - H
6. Oct - ? - G
7. Nov - ? - A
8. Dec - Loon - ? (Since G is 6th, Loon is 3rd (May) or 8th (Dec). If Loon is 8th (Dec), then the remaining person at 8th is D or C. Since D is not the first, D cannot be in March if C is in March, etc.)
Let's check if D is not the first one to study. D can be 8th or 2nd.
If D is 8th, then C is 2nd (March). So C studies Ostrich.
Let's check the options:
- "C and the one studying about Ostrich" is one of the options, which matches C at March studying Ostrich!

Therefore, the combination "C and the one studying about Ostrich" is correct.