酚试剂分光光度法检测室内空气中甲醛，采样所用的吸收液为（）。

A、蒸馏水

B、酚试剂吸收液原液

C、酚试剂吸收液

D、0.005%硫酸溶液

To manage a project including （）.

A．identity the request and make sure the clarity and achievable aim

B．balance the request of quality，scope，time and fee

C．make the technology regulation explaination，plan and means befit for different requests and expectation of all kinds of stakeholders

D．all of above