Mobile phones have made possible for us to reach out to the farthest corners of the world

问题补充：

Mobile phones have made possible for us to reach out to the farthest corners of the world from our homes.

A. them

B. that

C. this

D. it

答案：

A. them

B. that

C. this

(答案→)D. it

解析：考查it作形式宾语。但句子中的宾语从句内容较长时，可以用it代替从句内容放于动词后面，实际宾语放到句子末尾。本句中it指代to reach out to the farthest corners of the world from our homes.故选D。其它选项没有这个用法。