介绍家庭成员This is my... — 英语选择题
题目
Lily 指着家庭照片说："This is my father. This is my mother." 最后她指着照片上一位年长的男士说："This man is my father's father. Which sentence is right?（哪句话是对的？）"
A. This is my brother.
B. This is my grandfather.
C. This is my sister.
D. This is my grandmother.