Other genetic similarities suggested they all ________ a single, common ancestor about 300 years ago.

A.had B.have had C.have D.had had

 

A

【解析】A 考查動(dòng)詞時(shí)態(tài)。suggest在該句中意為“表明,暗示”,而非“建議”,所以賓語從句中不用虛擬語氣。因?yàn)橘e語從句的時(shí)間狀語為about 300 years ago,故該句用一般過去時(shí)態(tài),選A項(xiàng)。

 

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