请教nn一道语法题...谢谢:)

Although Ms.Bakara had prebiously emphasized that she could not speak for other Black people , she ventured to do so on this one occasion because she firmly believed that many minority people , likely most,would agree with her .

A do so on this one occation because she firmly believed that many minority people, likely most,would agree.

B  speak on this one occasion since she firmly believed that many minority people ,likely most ,would have agreed

C  so speak on this one occasion due to her firmly believing that many minority people , even most , would likely agree

D   do so on this one occation because she firefly believed that many minority people ,if not most , would agree

E   do so on this one occasion since she firmly believed many minority people ,and even most ,would likely agree

     为什么答案是d呢？

1.speak on in B and so speak on  in C are wrong.It's easy.

2.in A,what can the phrase--likely most  modify ?

3.in E,because is better than since.and that is omitted.and even most is ungrammatical.

是不是 likely most 是错误表述?

   当然还有speak on