15. The computer software being designed for a project studying Native American access to higher education will not only meet the needs of that study, but also has the versatility and power of facilitating similar research endeavors.

(A) but also has the versatility and power of facilitating

(B) but also have the versatility and power to facilitate

(C) but it also has the versatility and power to facilitate

(D) and also have the versatility and power of facilitating（B）

(E) and it also has such versatility and power that it can facilitate

动词的主语是什么?为什么要用HAVE呢?