---Who is that boy?-- He is my .A. father B. brother C. grandfather

问题补充：

---Who is that boy?

---- He is my .

A. father B. brother C. grandfather

答案：

解析：句意：那男孩是谁？他是我的弟弟。Father父亲；brother兄，弟；grandfather爷爷。根据问句中that boy可知该选B。