人工开采较稳固的矿岩时，工作阶段坡面角不大于。（）
A.15°
B.45°
C.50°
D.80°
参考答案：C
He withdrew from political life and____ he was soon forgotten.
A．as a consequence of
B．as a consequence
C．as a result of
D．as result
青春期从什么时期开始到什么时期结束？
