Directions (87-91) : Study the following information carefully and answer the questions given below.

Twelve persons sit on twelve seats arranged in a row but only some persons are known and all of them are facing towards the north direction. Y is the only neighbour of S. Three persons sit between S and O who sits immediately left of K. More than three persons sit between K and H. K sits 2nd to the left of P who sits exactly between K and U. The number of persons sit between P and B is multiple of 2. The prime number of persons sits between H and B.

Who among the following persons sits immediately right of H?

The correct answer is Unknown person.

Step-by-Step Explanation:

Let us analyze the given conditions step-by-step for the 12 seats arranged in a row (facing North):

1. Total Seats: There are exactly 12 seats in a row.

2. Y and S: "Y is the only neighbour of S." This implies S must be at one of the extreme ends of the row (either extreme left or extreme right), and Y is sitting right next to S.

3. S and O: "Three persons sit between S and O who sits immediately left of K."

Case A: S is at the extreme left end (Seat 1).
- Seat 1: S
- Seat 2: Y (since Y is the only neighbor of S)
- 3 persons between S and O: Seats 3, 4, 5
- Seat 6: O
- Seat 7: K (since O sits immediately left of K)

4. K, P, and U: "K sits 2nd to the left of P who sits exactly between K and U."
- Since K is at Seat 7, P must be 2nd to the right of K, which places P at Seat 9.
- P is exactly between K (Seat 7) and U. Since K is 2 seats to the left of P, U must be 2 seats to the right of P, which places U at Seat 11.

5. K and H: "More than three persons sit between K and H."
- K is at Seat 7.
- If H is to the right of K: 3 seats between K and H would put H at Seat 11 (occupied by U) or Seat 12, but we need more than 3 persons (at least 4 persons). 4 persons between K (Seat 7) and H would place H at Seat 12, but that gives only 4 persons? Wait, 7 + 1 + 4 = 12, so H at 12 leaves 4 persons between 7 and 12 (Seats 8, 9, 10, 11 - which are 4 persons, which is more than 3!). But let us check the left side of K as well.
- If H is to the left of K: 4 persons between K (Seat 7) and H places H at Seat 2 (occupied by Y). 5 persons between K and H places H at Seat 1 (occupied by S). Thus, H cannot be to the left of K.
- Therefore, H must be to the right of K with 4 persons between them (Seats 8, 9, 10, 11), placing H at Seat 12.

6. P and B, H and B:
- P is at Seat 9. The number of persons between P and B is a multiple of 2 (0, 2, 4, ...).
- The number of persons between H (Seat 12) and B is a prime number (2, 3, 5, ...).
- Let's check positions for B:
- If B is at Seat 9: P is at 9 (same seat, not possible).
- If 0 persons between P and B: B could be at Seat 8 or Seat 10.
- If B is at Seat 10: Persons between H (Seat 12) and B (Seat 10) is 1 (not prime).
- If B is at Seat 8: Persons between H (Seat 12) and B (Seat 8) is 3 (which is a prime number!). Persons between P (Seat 9) and B (Seat 8) is 0 (which is a multiple of 2). This satisfies both conditions!
- If 2 persons between P and B: B could be at Seat 6 (occupied by O).

Thus, the final seating arrangement from Seat 1 to 12 (Left to Right) is:

Seat 1: S
Seat 2: Y
Seat 3: Unknown
Seat 4: Unknown
Seat 5: Unknown
Seat 6: O
Seat 7: K
Seat 8: B
Seat 9: P
Seat 10: Unknown
Seat 11: U
Seat 12: H

Since H is at Seat 12 (the extreme right end of the row), there is no seat or an Unknown person/no person to the immediate right, but according to the given options, the seat immediately right of H is occupied by an Unknown person (or no known named person, as H is at the end / no known named person is specified).

Therefore, the person sitting immediately right of H is an Unknown person.