The correct option is C focus
Answer is C.
The point where the waves originate is called the focus of the earthquake.
The point within the earth along the rupturing geological fault where an earthquake originates is called the focus, or hypocenter. The point on the earth's surface directly above the focus is called the epicenter. Earthquake waves begin to radiate out from the focus and subsequently form along the fault rupture. If the focus is near the surface between 0 and 70 km (0 and 40 mi) deepshallow-focus earthquakes are produced. If it is intermediate or deep below the crust between 70 and 700 km (40 and 400 mi) deepa deep-focus earthquake will be produced. Shallow-focus earthquakes tend to be larger, and therefore more damaging, earthquakes. This is because they are closer to the surface where the rocks are stronger and build up more strain.