The Earth is an oblate spheroid and not a perfect sphere. This is because 1. the Earth has a rotational motion and the rotational speed increases as one goes from the Poles towards the Equator. 2. the Equator experiences greater gravitational pull from the Sun. 3. the intensity of sunlight received at the Equator is greater than that at the Poles. Select the correct answer using the code given below:

The Earth's shape as an oblate spheroid is primarily caused by its rotation on its axis. As the Earth rotates, it generates a centrifugal force that acts outward from the axis of rotation [c1, t3]. This force is directly proportional to the distance from the axis; therefore, while the angular velocity remains constant, the tangential rotational speed and the resulting centrifugal force increase from the poles toward the equator [c1, c2, t8]. This outward force at the equator causes the planet to bulge, while the poles remain relatively flattened [c1, t5]. Statement 2 is incorrect because the gravitational pull is actually weaker at the equator due to its greater distance from the Earth's center [c1, t2]. Statement 3 is incorrect because the intensity of sunlight (insolation) affects climate and temperature but does not determine the physical geoid shape of the solid Earth [t9].

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 18: Latitudes and Longitudes > The Shape of The Earth and Latitudinal Heat Zones > p. 241
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 7: Tectonics > Forces Behind The Drifting Of Continents (According to Wegener) > p. 95
3. [3] https://en.wikipedia.org/wiki/Equatorial_bulge