问题
单项选择题
It was now clear that no such weapons were manufactured and none been found. ()
A. was found
B. were founded
C. has been found
D. have been founded
答案
参考答案：A
解析：
时态应用。
"and"连接的两部分是并列关系，时态应一致，因而排除C、D。found是find的过去式，表“发现”；founded是found的过去式，表“建立，创立”，根据题干意思，本题应选A。