[求助]有關it的指代問題

61.   The aim of the new regulations is to make it easier for prospective homeowners to have funds available for energy improvement in their new houses.

(A) to make it easier for prospective homeowners to have

(B) to make easier for prospective homeowners the having of

(C) making it easier for prospective homeowners so they can have

(D) that prospective homeowners more easily can have（A）

(E) for prospective homeowners to more easily have

因為我覺得it冇所指,所以選e,但答案是a. 請問it指什麼?

什麼時候可以有it,什麼時候不可?

找到不能加it時再補上

Thanks

210.
                If additional deposits of oil are found, it will expand the amount that can be used as fuel and reduce the price of oil, even if the deposits are not immediately tapped.

(A) it will expand the amount that can be used as fuel and reduce the price of oil

(B) the amount that is able to be used as fuel will expand and the price of oil be reduced

(C) it will cause an increase in the amount that is able to be used as fuel and a reduction in the price of oil

(D) the amount that can be used as fuel will increase and the price of oil will drop（D）

(E) it will increase the amount of oil that can be used as fuel and cause a drop in the price

剛找到一個不能用it的例子.

為什麼上面61可, 這裡不可?