题目

DNA分子经过诱变，某位点上一个正常碱基(设为 P)变成了尿嘧啶，该DNA连续复制两次，得到的4个子代DNA分子相应位点上的碱基对分别为U—A、A—T、G—C、C—G，推测“P”可能是 A．胸腺嘧啶   B．腺嘌呤 C．胸腺嘧啶或腺嘌呤  D．胞嘧啶   答案：D ________ this road and you’ll get to the cinema quickly.      A. To follow                   B. Following               C. Follow                    D. Followed