快速原型的主要问题在于（）。

A、缺乏支持原型开发的工具 

B、要严格控制原型构造的迭代 

C、终端用户对原型不能理解 

D、软件的测试和文档更新困难

. —— So you think that listening to the music has a great effect on you.

—— ________, my dear. I feel relaxed when listening to it.

A．Hopefully

B．Almost

C．Exactly

D．Eventually