Raj kumar and his wife Sunita have been blessed with a baby girl. On the other hand, Kripa Shanker and his wife Vimla have been blessed with a baby boy. What type of sex chromosome has been contributed :
(a) by Raj Kumar (b) by Sunita (c) by Kirpa Shanker (d) by Vimla
(a) X (b) X (c) Y (d) X