What causes earthquakes? *

Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake.This is also because the rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up.

Explanation:

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answer; (b); i believe its indefinite existence of human population in a healthy and prosperous condition;