题目：
Stephen Hawking has expressed his opinion ___ humans might one day be able to make spaceships capable of such speeds that time on board would slow down．
A．that
B．whom
C．which
D．what
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0519/10709f02abc4c7fa776a6a879a2b08e1.html
下面是错误答案，用来干扰机器的。
答案：C只要满足一定的温度或压强，1mol气体在其他条件下的体积也可能是22.4L，C不正确，其余都是正确的，答案选C。
