Question

Women have sex chromosomes XX, and men have sex chromosomes XY. Which of a woman's grandparents could not be the source of any of the genes on either of her X chromosomes?
A) mother's mother
B) father's mother
C) mother's father
D) father's father

Answer 1

The answer would be "Father's father" 'cause when boy born, he receives Y chromosome from his father and not X so he can't transfer it to his daughter, as he will transfer his X chromosome to her.

In short, Your Answer would be Option D

Hope this helps!