Seven persons — A, B, C, D, E, F and G — are attending an event one after another, but not necessarily in the same order.
G attends the event three persons after C. B attends the event immediately before C. Only one person attends the event between B and E. D attends the event four persons after E but before A. Three persons attend event between A and F.

Who among the following is the second person in sequence to attend the event?

The correct option is F.

Step-by-Step Explanation:

Let the 7 positions of the persons attending the event in sequence from first to last be numbered 1 to 7.

1. Analyze the clue about G and C:
"G attends the event three persons after C."
This means if C is at position $x$, then G is at position $x+3$ (there are 2 persons between C and G).

2. Analyze the clue about B and C:
"B attends the event immediately before C."
So, the order is B, C, _, _, G.

3. Analyze the clue about B and E:
"Only one person attends the event between B and E."
This means E can be 2 positions before B or 2 positions after B.
- If E is after B, E would occupy the position between C and G (i.e., B, C, E, _, G).
- Let's check the next clue: "D attends the event four persons after E". If E is at position $y$, D is at position $y+4$.
If E is placed after B as B, C, E (positions 1, 2, 3), then D would be at position $3+4=7$. Let's test this sequence:

Let's place B at position 1:
- Position 1: B
- Position 2: C (immediately after B)
- Position 3: E (one person, C, between B and E)
- Position 4: F / A
- Position 5: G (three persons after C: C is 2, so G is 5)
- Position 7: D (four persons after E: E is 3, so D is 7)

Now let's check the remaining positions: 4 and 6 for A and F.
The clue says: "D attends the event four persons after E but before A."
Since D is at position 7, A cannot be after D. So D being at position 7 makes it impossible for D to be before A!

Therefore, E must be placed before B.
Since there is 1 person between B and E, if B is at position $k$, then E is at position $k-2$.

Let's test position assignments with E before B:
- If E is at Position 1:
- Position 2: (One person between E and B)
- Position 3: B
- Position 4: C (immediately after B)
- Position 5: D (four persons after E: E is 1, so D is $1+4=5$)
- Position 7: G (three persons after C: C is 4, so G is $4+3=7$)

Remaining positions to fill: 2 and 6 with A and F.
Clue: "D attends ... before A."
Since D is at Position 5, A must be at Position 6 (after D).
Clue: "Three persons attend event between A and F."
Since A is at Position 6, F must be at Position $6-4=2$ (so there are 3 persons—positions 3, 4, 5—between F and A).

Let's verify the complete sequence from 1st to 7th:
1. E
2. F
3. B
4. C
5. D
6. A
7. G

Verification of all conditions:
- G attends 3 persons after C: C is 4th, G is 7th ($7-4=3$). (Correct)
- B attends immediately before C: B is 3rd, C is 4th. (Correct)
- Only 1 person (F) between B (3rd) and E (1st). (Correct)
- D (5th) attends 4 persons after E (1st) ($1+4=5$) and before A (6th). (Correct)
- Three persons (B, C, D) attend between F (2nd) and A (6th). (Correct)

Thus, the second person in sequence to attend the event is F.