The correct answer is: Anil is Bimal’s grandson.
Deepak is the son of Prem, and Bimal is Prem’s father. This means that Anil is Deepak’s brother, and Deepak is Prem’s son. Therefore, Anil is Bimal’s grandson.
A son is a male child of a parent. A grandson is a male child of a son or daughter. A brother is a male sibling. A grandfather is a male parent of a parent.
In this case, Anil is a male child of Deepak, who is the son of Prem. This means that Anil is Bimal’s grandson.