单选题 What has caused the pollution problem?

A、 Careless methods of production.
B、 Lack of consumer demand for environment friendly products.
C、 Millions of tons of glass, paper, plastic and metal containers are produced.
D、 Both[A]

【正确答案】 D

【答案解析】[解析] 由文章第一段第二句“Careless methods of production and lack of consumer demand for environment friendly products have contributed to the pollution problem可以得出本题答案为D。