Even though Jack has failed many times in his experiment,he holds a belief _____ he will succeed one day if he carries o
问题描述：
Even though Jack has failed many times in his experiment,he holds a belief _____ he will succeed one day if he carries on with it.
A.what B.which C.whether D.that
答
D.that
that引导同位语从句, 说明belief的内容是什么.
句意: 尽管杰克的实验失败了很多次,但他还是坚信,如果他把实验继续做下去, 总有一天他会成功的.