我觉得判断的标准时but后面有没有主语，如果有主语，那么是个独立的主语，就是单独的句子，加that和前面的that并列，如果没有主语，那和前面的是一句话，就是都是前面的that下面的
-- by 会员 红尘道士 (2010/7/2 11:00:29)
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 preceded with ultrasound was or was not any better for heart attack patients than the balloon procedure by itself.
A. more research was needed to determine that balloon angioplasty preceded with ultrasound was or was not any better for heart attack patients than
B. more research was needed for determining whether or not balloon angioplasty preceded by ultrasound is any better for heart attack patients than is
C. that more research was needed to determine whether balloon angioplasty preceded by ultrasound is any better for heart attack patients than
D. that more research was needed to determine that balloon angioplasty preceded with ultrasound was any better for heart attack patients than
E. that more research was needed for determining that balloon angioplasty preceded by ultrasound is or is not any better for heart attack patients than is
Ｃ是正确答案，但agree that ……but that总觉得怪怪，B是因为多了or not才不选的么？
-- by 会员 yousk (2010/7/1 21:24:14)