----What will we do if we want to develop our village ?-A lot of roads . I think .A. h

问题补充：

----What will we do if we want to develop our village ?

---- A lot of roads . I think .

A. have to build

B. are build

C. must be built

D. will build

答案：

A. have to build

B. are build

(答案→)C. must be built

D. will build

解析：句意：如果我们想要发展我们的村庄，我们应该做什么？——必须修许多公路，我认为。结合语境可知下文主语为动作的对象，故用被动语态。选项B描述的是客观状态，语义不符。故选C。