They took （）measures to prevent poisonous gases from escaping.

They took （）measures to prevent poisonous gases from escaping.
A、fruitful
B、beneficial
C、efficient
D、effective
【正确答案】：D
【题目解析】：fruitful有成效的，多产的；beneficial有益的；efficient高效的；effective有效的，起作用的。因此选D。本题句意为：他们采取了有效措施来防止有毒气体泄漏。