There is a family of six members M, P, R, S, T and Q. There are two married couples in that family and the family is of three generations. M is only grand-son of P, who has two children. Q is the sister-in-law of R, who is the only daughter of S. P and S are married couple. M is not the son of R. How is M related to R?

• A. Cousin
• B. Nephew
• C. Niece
• D. Son-in-law