The foreign exchange market is: （ ）
选项：

A:open for only 12 hours in a day.
B:the market never sleeps.
C:open for most of the day but closes for 3 hours each day—between 2:00 AM and 5:00 AM Greenwich Mean Time.
D:open during normal business hours (9:00 AM to 5:00 PM, local time) in each of the primary locations from which it operates: Tokyo, London, and new York.