求教大全166。

1.        Because of the enormous research and development expenditures required to survive in the electronics industry, an industry marked by rapid innovation and volatile demand, such firms tend to be very large.

(A) to survive

(B) of firms to survive

(C) for surviving

(D) for survival（B）

(E) for firms’ survival

B中的"of"和require的关系是什么？