By what name is the point of origin of earthquake known ?

The correct answer is (a) Focus.

The focus is the point within the Earth where an earthquake originates. It is also known as the hypocenter. The epicenter is the point on the Earth’s surface directly above the focus.

The generation point is the point where the energy released by an earthquake is first generated. The earthquake point is the point where the earthquake is first felt.

The focus is always located below the surface of the Earth, while the epicenter is always located on the surface of the Earth. The generation point and the earthquake point can be located either below or on the surface of the Earth.