单项选择题
A.Pick up speed where the channel widens B.Run slower in the center of the channel C.Hug the inside of a bend D.Cause the greatest depth of water to be along the outside of a bend
A.at times of new and full Moon B.when the Earth，Moon，and Sun are lying approximately on the same line C.when the Moon is between first quarter and full and between third quarter and new D.when the Moon is between new and first quarter and between full and third quarter
A.Moon is in its first quarter and third quarter phases B.Sun and Moon are on opposite sides of the Earth C.Moon's declination is maximum and opposite to that of the Sun D.Sun and Moon are in conjunction