Things made of plastic are usually , but they are to get polluted.
A. cheap; easy
B. cheap; easier
C. cheaper; easy
D. cheaper; easier
网友回答
A. cheap; easy
B. cheap; easier
C. cheaper; easy
(答案→)D. cheaper; easier
解析：根据句意可知塑料制品相对比较便宜但是也会带来污染，有比较之意故选D.