To be successful，the organization should be committed to addressing the management of risk______．

A．just before a meeting with a client

B．proactively and consistently throughout the project

C．as soon as time and cost estimates are ready

D．early in the execution phase

浓缩白细胞的制备方法。（）

A.沉降法和离心法。

B.机采法和离心法。

C.机器洗涤法和沉降法。

D.机采法和手工法