Explanation:

Let’s break down the question step by step:

- Arrangement:

- Girls: A, B, C, D (facing south, so their left/right is our right/left).

- Boys: P, Q, R, S (facing north, so their left/right matches our view).

- Clues:

- *P and C are diagonally opposite.* So if C is 1st girl, P is 2nd or 4th boy, depending.

- *A is second to the right of C.* Since the girls face south, "right" to them is our left.

- *S is the immediate neighbour of Q and R.* Only possible if S is between Q and R.

- *C is facing R.*

Let’s arrange:

- Let’s put C first. If C is at position 1 (leftmost), then A is 2nd to C's right -> C, D, A, B (from left to right).

- C faces R, so R must be in front of first position (C).

- P is diagonally opposite to C: C (1st), P should be at 2nd or 4th boy‘s position.

- S is neighbour of both Q and R, so the only possible is Q, S, R.

So, arrange boys: (since S between Q & R). Positions for boys must be such:

- R facing C (position 1). That puts R in position 1.

- Then S can be in position 2, and Q in position 3, P in position 4.

Let’s map:

| Girls | 1 (C) | 2 (D) | 3 (A) | 4 (B) |

|-------|--------|--------|--------|--------|

| Boys | R | S | Q | P |

Now, let's check options:

- 1. D and P: D faces S, not P (D is position 2, P is 4).

- 2. B and S: B faces P, not S.

- 3. A and Q: A in 3rd position faces Q in 3rd position.

- 4. D and S: D faces S. D (2) faces S (2).

Correct Options:

Both options 3 (A & Q) and 4 (D & S) are correct, but since you asked “Which of the following pairs ... is definitely correct?” and if only one to choose, option 3 is correct, as per the arrangement.

(Option 3: AQ)