（）构成了炮兵声测侦察的理论基础。
A、“双耳效应”
B、“双目效应”
C、“单耳效应”
D、“单目效应”
参考答案：A
He always with his brother about some little things, and their mother is angry with them. [ ]
A. quarrels
B. debates
C. helps
D. discusses
阿司匹林中存在哪种杂质可引起过敏反应（）.
A．
B．
C．
D．
E．
