求教!新概念英语第三册的一道选择题:

问题描述:

求教!新概念英语第三册的一道选择题:
Lesson10 .④_____were 1,316 passengers and a crew of 891.
a.On her board b.On board her c.Boarding her d.On boarding her
为什么是选b?

有人问过这个问题了.“以下都是可以的:1)On her board were 1316 passengers.2)On board there were 1316 passengers.3)On board of her were 1316 passengers.” 另外也有人认为her作为对于“船”之类的代词....