I found him sitting in his chair，completely          a magazine．

A．absorbing

B．being absorbed in

C．absorbed in

D．absorbing in

对于全向型天线，要求（）安装；对于方向型天线，其（）和（）要符合设计文件的规定。

A、垂直、指向、俯仰角

B、指向、垂直、俯仰角

C、垂直、俯仰角、垂直

D、垂直、俯仰角、指向