求解GWD-TN-7-Q3？再次看到两个不同答案

麦兜woo

Because of wireless service costs plummeting in the last year, and as mobile phones are increasingly common, many people now using their mobile phones to make calls across a wide region at night and on weekends, when numerous wireless companies provide unlimited airtime for a relatively small monthly fee.

A. Because of wireless service costs plummeting in the last year, and as mobile phones are increasingly common, many people

B. As the cost of wireless service plummeted in the last year and as mobile phones became increasingly common, many people

C. In the last year, with the cost of wireless service plummeting, and mobile phones have become increasingly common, there are many people

D. With the cost of wireless service plummeting in the last year and mobile phones becoming increasingly common, many people are

E. While the cost of wireless service has plummeted in the last year and mobile phones are increasingly common, many people are

看到两个不同的答案D和E，标准答案到底是哪个呢？

麦兜woo

B的话,后面那句话many people...没有谓语,不知道可不可以这样理解

Ravens

为什么B选项不对？请教

louis_huang

个人觉得D对.
GMAT中有原句时态不轻易改变原则, in the last year不能看作是完成时的标志, 而且句意也没特别明显的完成时态的意思，所以E这里错了;
D中用了with+n.+分词的独立主格结构，且and前后平行对称，比E要好。