With the time went on, I found she had ___.

A．a few white hair

B．some white hair

C．several white hairs

D．much white hair

沙尘天气光线暗淡影响观察时，应开启近光灯、示廓灯、后位灯，必要时开启危险报警闪光灯。同时，能见度在100～200m时，时速应控制在（）km以内，夜间时速应控制在30km以内，满载大客车和重载大货车更应降低车速。

A.10

B.20

C.30

D.40