is a good idea to bring your camera because you may want to take photos of the autumn leav

问题补充：

is a good idea to bring your camera because you may want to take photos of the autumn leaves.

A. This

B. It

C. That

D. What

答案：

A. This

(答案→)B. It

C. That

D. What

解析：考查代词的用法。当不定式短语较长时，通常用it作形式主语放在句首，将真正主语不定式结构放在句子后部。故选B。