man says to another man, This boy is the son of the only son of my father. What is the relation between the boy and the man?
Hello student as the man said the boy is the son of the only son of his father then he must be his son the blood relation between the boy and the man is father and son.
You can practice blood relation questions for reasoning part of entrance examination the more you practice the more you'll learn.
Feel free to comment if you have any doubt
Good luck