Earth is not completely spherical in nature. It is elliptical in nature. The radius along the equator is more than the radius along the poles.
The earth processes two radiuses along the two axes that is the north-south axis and the east west axis. The radius of the earth along its equatorial Axis that is the east-west axis is \[6378.1\] kilometre and the polar eight years or we can say the radius around the polar axis is \[6356.8\] kilometre. The polar access is also known as the North South axis. Twice of the radius will give us the value of diameter hence the diameter along the equatorial Axis east-west axis will be \[6378.1 \times 2 = 12756.2\].
Thus, the correct option is C.
Earth is the third planet from the sun. Earth is the only planet where life exists. The majority of the Earth's surface is covered with water bodies and twenty nine percent of earth surface as land. The earth is little bit extended towards the equator then the poles that is why the radius at the equator is more than the radius at the poles. This makes the diameter at the equatorial region 43 km more than the diameter at the pole. About chemical composition, the earth consists of many compounds in its crust for example silica, Alumina, lime, magnesia, iron oxide, sodium oxide, potassium oxide, titanium dioxide, manganese oxide.
Fields that are present in the earth, that is, gravitational field and magnetic field. Earth shows both rotation and revolution; it rotates on its own axis and also orbits around the sun simultaneously.