题目

A man heard that a certain government wanted a clerk, so wrote and asked for the position. But while he was waiting for an answer, a friend of his introduced him to the head of the department, who gave him the job. Several months later, while the man was working in the department, he got a letter that had been sent to him from the place he used to live in. This letter said, “Dear sir, We are sorry to have to tell you that we cannot offer work in this department because we do not think that you would be able to do the work successfully.                             下列物质对应关系不正确的是（ ）A.淀粉﹣﹣葡萄糖B.蛋白质﹣﹣氨基酸C.核酸﹣﹣核苷酸D.脂肪﹣﹣甘油