250. (GWD30-Q29)Researchers agreed thatthe study of new treatments for heart attack patients was extremely importantbut more research was needed to determine that balloon angioplasty precededwith ultrasound was or was not any better for heart attack patients thanthe balloon procedure by itself. C that more research was needed to determine whether balloon angioplastypreceded by ultrasound is any better for heart attack patients than (Correct) 我以"is"时态和前面was不一致就排除了。看了preps的解释才 明白换一种语义context理解,这样写完全是正确的。
D that more research wasneeded to determine that balloon angioplasty preceded with ultrasound was anybetter for heart attack patients than (wrong) 我选了这个