Evan’s son-in-law is married to Mahesh and Mahesh has only one sibling.

Hence, Mahesh is the daughter of Evan but Evan’s gender cannot be found.

Ramesh’s father-in-law has two granddaughters.

Since there are only three generations, Ramesh has to be in the second generation (as he has a father-in-law and this father-in-law has two granddaughters).

Hence, the two granddaughters are the children of either Mahesh or her sibling.

Champak’s brother-in-law has two daughters and Champak is unmarried.

Hence, Champak has to be the unmarried sibling of Mahesh and Ramesh is the husband of Mahesh.

We have already identified the four females as Mahesh, Mahesh’s two daughters and Mahesh’s mother (as each child has both parents present).

Hence, Champak has to be male i.e. Champak is the brother of Mahesh and son of Evan.

Suresh’s brother has only one nephew and Suresh is not Mahesh’s mother. Hence, Suresh is Mahesh’s father and Evan is Mahesh’s mother.

Since Bandhu has only one niece and Suresh’s brother has only one nephew, Bandhu is Suresh’s brother (as this person has one niece and one nephew). Hence, the remaining people – Ajay and Dharmesh – are the daughters of Mahesh. The overall family tree is shown below:

Hence, Ajay is the daughter of Ramesh i.e. the statement in option d is true. Hence, option D.