求教GWD30-Q29

Miamiami

researchers agreed that the study of new treatments for heart attack patients was extremely important but more research was needed to determine that balloon angioplasty with ultrasound was or was not any better for heart attack patients that  the balloon procedure by itself.

答案 C  that more  research was needed to determine whether balloon angioplasty preceded by ultrasound is any better for heart attack patients than

这里的is 怎么理解呢？？整个语境是过去时啊？前面那个并列的分句也是过去时啊？？

maratderk

顶这个问题啊

skyemotion

is是这个从句的谓语
whether balloon angioplasty preceded by ultrasound is any better for heart attack patients than

意思是验证一个BA是否更好。陈述一个事实，所以用is，
但是我想这个is并不是排除选择最佳答案的唯一亮点。
可以跳过这个点选择其他的。

lllmmm

现在并不知道 balloon angioplasty preceded by ultrasound 是不是有前途，故不能用过去时，只能用现在或将来时