The other day，my friend John drove his car down the street at I thought was a dangerous speed and surprised everyone in the car.
A. which，that
B. which，it
C. as，which
D. what，that
网友回答
A. which，that
B. which，it
C. as，which
(答案→)D. what，that
解析：D点拨 what 引导宾语从句，that 指代上文提到的内容，在后一句中做主语，前后是and连接的并列句。