— When did you go to bed last night?

— Very late. I didn't go to bed _____ my father came back. [ ]

A. until

B. since

C. while

D. after

下列关于小规模纳税人的说法正确的是（）。

A.小规模纳税企业的增值税征收率一律为3%

B.小规模纳税企业销售商品价格通常为含税价

C.小规模纳税企业销售商品价格通常为不含税价

D.小规模纳税企业的增值税税率一律为3%