scores of times , but he still couldn’t understand it ．
A. Having explained
B. Having been explained
C. Though it was explained
D. It was explained
网友回答
A. Having explained
B. Having been explained
C. Though it was explained
(答案→)D. It was explained
解析：考查句子结构，两句话中间有but，说明是并列句，前面也是简单句，AB是分词，只能做非谓语，C是让步状语从句，选D，句意是：这已经被解释很多次了，但他还是没懂。选D，