Explanation:

Let’s break down the information:

- S is married to A, who is the mother of G.

- R is the sister-in-law of A.

- K is the grandson of P and the only son of R.

- P has one granddaughter.

Let's map the connections:

- A (female) is married to S.

- G is A's child, so S is also G's parent.

- R is A's sister-in-law ? so R is S's sister, or S's brother’s wife.

- K is R's only son and P’s grandson.

- P has one granddaughter ? G must be the granddaughter, so G is female.

Combining all:

- P (grandparent)

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R (daughter) S (son)

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K (R's son) A (S's wife)

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G (girl)

So, S is the son of P.

Correct Option:

- Option 1: Son

Explanation:

- S is P’s son, as R (P’s daughter) and S both are P's children.

- S is married to A; A is the mother of G (the only granddaughter).

- K is P's grandson through R.

- Option 2 and 3 don’t fit since S is not P's father/grandfather.

- Option 4 (Aunt) is not possible.

Final Answer:

- Option 1: Son