If X is the brother of the son of Y`s son, how is X related to Y ?
Option:
Justification:
Son of Y's son -- Grandson;
Brother of Y's grandson -- Y's granson.

If X is the brother of the son of Y`s son, how is X related to Y ?
Justification:
Son of Y's son -- Grandson;
Brother of Y's grandson -- Y's granson.