Have you any idea _______?

A．that how we can improve the English level within 4 months

B．that how can we improve the English level within 4 months

C．how can we improve the English level within 4 months

D．how we can improve the English level within 4 months

出口加工区顾名思义，是为促进加工贸易出口而设立的。因此出口加工区的制成产品不能销往境内，只能出口。