（）is not a type of tide.

A.slack water when upbound
B.shallow water
C.a cross current
D.a head current

A.Moon being at its maximum declination
B.Moon crossing the equator
C.Sun and Moon both being near 0°declination
D.Moon being at perigee

A.One hour after the predicted time
B.At the predicted time
C.30 minutes before flood，one hour after an ebb
D.30 minutes before the predicted time