it would be silly to argue any longer ．
A. Was that true
B. If that was true
C. Should that be true
D. Could that be true
网友回答
A. Was that true
B. If that was true
(答案→)C. Should that be true
D. Could that be true
解析：考查虚拟语气。首先排除A B A里面的was应该用were，从句意上看排除D。正确答案是C。If that should be true, 去掉if 句子倒装。句意：如果这应该是真的，继续争吵这个是很傻的。