(C)be available to V 는 정답이 될 수 없는 건가요?

02번 문제(p.313) :

Although stock options were previously offered only to management, the rank-and-file are now ------ to purchase options.

(A) appropriate

(B) eligible

(C) available

(D) befitting

명확한 답변 부탁드려요ㅎ