单选题 It was now clear that no such weapons were manufactured and none been found .
【正确答案】 A
【答案解析】[解析] 本题考查句子时态和词义辨析。由于“and”连接的两部分属并列关系，所以，句子前后时态应一致，应为一般过去时。又因为find“发现”的过去式是found，founded是found“建立”的过去式，根据题意可知，A为正确答案。