移植心脏对低血压和低血容量引起心率的反应以下哪项是正确（）

A.低血压引起心率明显增快

B.低血容量心率明显增快

C.A和B

D.低血容量心率减慢

E.低血压和低血容量时心率变化不大

Including a contingency reserve in the project budget is intended to （）.

A．reduce the probability of scope changes

B．increase the probability of scope changes

C．reduce the probability of a cost overrun

D．increase the probability of a cost overrun