Option(4) is correct.

The required family diagram according to the given information is given below :

Here, we don't know the gender of R and Q, but T is definitely the granddaughter of Q.
Hence, the correct answer is option(4) i.e., T is the granddaughter of Q.
A and B are brothers. C and D are sisters. A's son is D's brother. How is B related to C?
A is B's sister. C is B's mother. D is C's father. E is D's mother. Then, how is A related to D?
Shanti’s daughter Chandini is married to Abhi. Anchal is married to Sandy, the grandson of Shanti. Abhi's grandson is Karan. Rashmi is the mother of Karan. Shaurya is Anchal's son. How is Shaurya related to Karan?