( )指能够适应环境变化的雇佣关系具有更高的效率。
A．自我利益的克制
B．对雇佣关系的投资
C．适应性
D．可靠性
参考答案：C
It is global warming, rather than other factors,_____ the extreme weather.
A．that have led to
B．which has caused
C．which are causing
D．that has led to
航天飞机是一种不可重复使用的载人航天运输工具。
