The mother asked her son _____. [ ]

A. what did he do the day before

B. where did he find his wallet

C. what time he got up that morning

D. that if he had finished his homework

堤身碾压时必须严格控制土料含水率。土料含水率应控制在最优含水率( )范围内。

A．±1%B．±2%
C．±3%
D．±5%