I asked him to _____ me a few minutes so that we could go over all the problem.

A．spend

B．save

C．spare

D．share

粉尘爆炸是指悬浮于空气中的可燃粉尘触及明火或电火花等火源时发生的爆炸现象。下列各组常见粉尘中，能够发生爆炸的是（）。

A.金属粉尘、煤粉尘、粮食粉尘、木粉尘

B.煤粉尘、粮食粉尘、水泥粉尘、棉麻粉尘

C.饲料粉尘、棉麻粉尘、烟草粉尘、玻璃粉尘

D.纸粉尘、煤粉尘、粮食粉尘、石英粉尘