Not only he but also we ______ right. That is to say, we as well as he ______ right. [ ]

A.are; are

B.is; is

C.are; is

D.is; are

读地球圈层结构示意图，完成下列小题。

关于图中各圈层的叙述正确的是（）

A．A、B、C、D为地球外部圈层，C为生物圈

B．地球内部圈层由E、F、G三部分组成

C．A、B、C、D、E共同形成了人类赖以生存的地理环境

D．地震波在F、G交界面上，传播速度减为0