—Why not ask Zhao Yu to play soccer with us?
—He has _______ grandmother. He has to stay at home to care for her.

A．an eighteen-year-old	B．a eighty-year-old
C．an eighty-years-old	D．an eighty-year-old

科目 英语   题型 单选题   难度 中等

知识点： 名词作定语