Question

____ can be seen in the chart right here, the air pollution level in the city has been increasing over the last months.

A．What

B．It

C．that

D．As

Answer 1

D

试题分析： 考查as引导非限制性定语从句。题意 正如我们所看到的，空气污染水平在上月一直在增长。As代指 the air pollution level in the city has been increasing over the last months，故选 D项。
考点 非限制性定语从句。