The periodic rise and fall of the sea level on the earth, gives rise to tides. This is related to

•     the position of the moon with reference to the earth and the gravitational pull exerted mainly by the moon and partly by the sun

•      infrared rays from the sun

•      ultraviolet rays from the sun

•      None of the above

Ans:
 the position of the moon with reference to the earth and the gravitational pull exerted mainly by the moon and partly by the sun