问题补充：
—Jack bought a new mobile phone the other day.
—?That’s his third one in just one month.
A. Had he
B. Did he
C. Does he
D. Has he
答案：
A. Had he
(答案→)B. Did he
C. Does he
D. Has he
解析：Did he?意为“是吗？”。根据所提供的情景Jack bought a new mobile phone the other day.可判断出要用一般过去时Did he did。
