After finishing_______his homework, Tom decided______a walk in the park.

A．to do;to take

B．doing; taking

C．doing; to take

D．to do; taking

产后泌乳主要依赖

A．雌激素下降'

B．孕激素下降

C．垂体泌乳素升高

D．吸吮刺激

E．垂体释放缩宫素