Assertion (A): The weight of a body decreases with the increase of latitude on earth Reason (R): The earth is not perfect sphere

The correct answer is D because the Assertion is false and the Reason is true.

The weight of a body actually increases as you move from the equator toward the poles increase in latitude. This happens for two reasons. First, because the earth is not a perfect sphere but an oblate spheroid, the poles are closer to the center of the earth than the equator. According to the law of gravitation, being closer to the center increases the gravitational pull. Second, centrifugal force due to earths rotation is maximum at the equator and zero at the poles. Since centrifugal force acts outward, it reduces the net weight at the equator.

Therefore, since the gravitational pull is stronger and centrifugal force is absent at the poles, a body weighs more at higher latitudes, making the assertion false. The reason correctly states that the earth is not a perfect sphere, which is a true statement.