题目

--I’m sure Andrew will win the first prize in the final.    ---I think so. He _____ for it months.    A. is preparing    B. has been preparing  C. was preparing    D. had been preparing    答案：B5．下列图片中的物理现象与所对应的物理知识相符的是（　　）A．光的色散B．光的折射C．光的反射D．光沿直线传播