It is believed that ________ December 21st, 1891, the first basketball game in history was played.

A．on

B．in

C．at

D．by

开挖前向裂缝内灌入（），以利掌握开挖边界。

A、水泥浆

B、混凝土浆

C、白灰水

D、泥浆