GWD一道语法，没弄明白什么意思，请教大家~~

Heavy commitment by an executive to a course of action, especially if it has worked well in the past, makes it likely to miss signs of incipient trouble or misinterpret them when they do appear.

A.      Heavy commitment by an executive to a course of action, especially if it has worked well in the past, makes it likely to miss signs of incipient trouble or misinterpret them when they do appear.

B.       An executive who is heavily committed to a course of action, especially one that worked well in the past, makes missing signs of incipient trouble or misinterpreting ones likely when they do appear.

C.      An executive who is heavily committed to a course of action is likely to miss or misinterpret signs of incipient trouble when they do appear, especially if it has worked well in the past.

D.      Executives’ being heavily committed to a course of action, especially if it has worked well in the past, makes them likely to miss signs of incipient trouble or misinterpreting them when they do appear.

E.       Being heavily committed to a course of action, especially one that has worked well in the past, is likely to make an executive miss signs of incipient trouble or misinterpret them when they do appear.

DEARS，能否帮忙解释一下，谢谢

答案选C哈

还有一道~~

GWD-12-Q41:

The first English settlers to establish a permanent colony in America did it not at Plymouth but along the shore of the James River west of Chesapeake Bay.

A.      it not at Plymouth but

B.       so not at Plymouth but

C.      not at Plymouth but instead

D.      not at Plymouth but did so

E.       it not at Plymouth but rather

选B，so not ,,but,是语法？

第一道，句子有明确主语的情况下用主动

所以就把主语为人的选出来

B去掉了原来的虚拟，所以错误

最后选C

第二道，第一批英国人do so

not 在
            Plymouth but在河沿岸（不是A   而是B）

谢谢啦，第二道明白了哈

第一道同楼上疑问，话虚拟语气it指的什么？