Seven persons A, B, C, D, E, F and G sit in a row facing north. They have different elements named copper, nickel, gold, mercury, aluminum, silver and iron. The information is not used in the same order as given.

The one who have gold sits third to the left of D, none of them sits at any of the extreme ends. E sits immediate right of the one who have gold. B and E sit adjacent to each other. The one who have iron sits second to the left of B. Two persons sit between G and F. The one who has mercury sits fourth to the right of G. The one who have copper sits immediate right of the one who has silver. The one who have nickel sits to the left of F and to the right of A.

C have which of the following element?

To find which element C has, let us reconstruct the seating arrangement step-by-step. There are seven positions, numbered from 1 to 7 from left to right.

Step 1: Determine the positions of Gold and D
The clue states that the person who has gold sits third to the left of D, and neither of them sits at the extreme ends (positions 1 or 7).
If Gold is at position 2, then D must be at position 5.
If Gold is at position 3, then D must be at position 6.
If Gold is at position 4, D would be at position 7, which is an extreme end and thus invalid.

Step 2: Place E and B
E sits to the immediate right of the one who has gold. B and E sit adjacent to each other. The one who has iron sits second to the left of B.
Let's analyze Case 1 (Gold at 2, D at 5):
E is at position 3. B must be at position 4 (since position 2 is occupied by Gold, and the person at position 2 cannot have both Gold and Iron if B is at 2).
If B is at position 4, then the person second to the left of B (position 2) must have Iron. However, position 2 already has Gold. Thus, Case 1 is invalid.
Let's analyze Case 2 (Gold at 3, D at 6):
E must be at position 4. B is adjacent to E, so B can be at position 3 or 5.
If B is at position 5, the person second to the left of B (position 3) must have Iron. But position 3 has Gold. So B cannot be at position 5.
Thus, B must be at position 3 (having Gold). The person second to the left of B (position 1) has Iron.

Currently, the arrangement is:
1: [Iron]
2:
3: B [Gold]
4: E
5:
6: D
7:

Step 3: Place G, F, and Mercury
Two persons sit between G and F. The one who has mercury sits fourth to the right of G.
If G is at position 1, Mercury is at 5, and F is at 4 (but E is already at 4).
If G is at position 2, Mercury is at 6 (so D has Mercury), and F is at 5 (leaving 2 persons, B and E, between G and F). This works perfectly.

The updated arrangement is:
1: [Iron]
2: G
3: B [Gold]
4: E
5: F
6: D [Mercury]
7:

Step 4: Place Silver and Copper
The one who has copper sits to the immediate right of the one who has silver.
Looking at the available adjacent slots for elements, only positions 4 and 5 are unoccupied by elements.
So, E (position 4) must have Silver, and F (position 5) must have Copper.

Step 5: Place Nickel, A, and C
The one who has nickel sits to the left of F (position 5) and to the right of A.
The remaining positions for elements are 2 and 7. Since Nickel is to the left of F, Nickel must be at position 2 (G has Nickel).
Since G (Nickel) is to the right of A, A must be at position 1 (A has Iron).
The remaining element is Aluminum, which must go to position 7. The only remaining person to place is C, who must sit at position 7.

The final completed arrangement is:
1: A [Iron]
2: G [Nickel]
3: B [Gold]
4: E [Silver]
5: F [Copper]
6: D [Mercury]
7: C [Aluminum]

Therefore, C has the element Aluminum.