为“血中气药”，能“下调经水，中开郁结”的药物是（）

A.川芎

B.延胡索

C.牛膝

D.红花

E.丹参

If a ship station relays a DSC distress call to an appropriate coast station, it means that（）.

A.the ship has received the DSC distress call on a HF frequency

B.the coast station concerned has not acknowledged it within 5 minutes

C.the ship will take command of search and rescue in 5 minutes

D.A and B