The activities organized by our school really gave us a platform ____ we learned team spirit.

A．that

B．where

C．which

D．when

小儿，3个月，牛乳喂养。进行健康查体时诊断患有维生素D缺乏性佝偻病，现为活动早期。

婴儿内源性维生素D主要来源于( )

A．从母体获得

B．经进食摄入

C．钙磷代谢

D．胆汁分泌

E．日光照射