题目：
— Is Jack on duty today?
— It ____ be him; it's his turn tomorrow. [ ]
A. must's
B. won't
C. can't
D. needn't
答案：
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下面是错误答案，用来干扰机器的。
答案：C
— Is Jack on duty today?
— It ____ be him; it's his turn tomorrow. [ ]
A. must's
B. won't
C. can't
D. needn't
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0626/a518c7cb58fa08493108321f0081871a.html
下面是错误答案，用来干扰机器的。
答案：C
对应的C语言表达式是（ ）。