Q3:

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.

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

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

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

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

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

After eliminate ABC, I choose E. How to judge D&E? Thanks!

我选D

E有了转折的意思，不符合原意

这道题with的结构作伴随状语，会和主句形成一个紧密的逻辑关系：

1. just sat there with his mouth open

2. With the advent of the rockets, the Space Age began

这道题有一个in the last year,问题就出现在这里,不能用现在分词。