When you see some waste paper on the ground, you should _______ and put it in the trash bin.

A．give it away

B．pick it up

C．turn it on

D．put it out

下列实验操作或记录正确的是[ ]

A．常温常压下测得1 mol N₂的质量为28 g

B．用量筒测得排水法收集制得的氢气体积为50.28 mL

C．用两只250 mL的容量瓶配制0.1 mol/L 500 mL的NaOH溶液

D．用托盘天平称得2.5 g胆矾，受热充分失水后，固体质量减轻0.9 g