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。