单选题Through so much trouble，h

单选题 Through so much trouble，he learned ________ everyone needed friendship and ________self confidence is important.A.that；/B./；/C.that；thatD./；what

C解析考查宾语从句的连接词。________ everyone needed friendship and ________self confidence is important.是两个并列的宾从，从句都不缺成分，所以用that引导，第一个that可以省略，第二个不可少，所以选C。

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