Final answer:
The magnitude of an earthquake decreases as distance from the epicenter increases because the energy of seismic waves decreases as they travel farther from the epicenter.
Step-by-step explanation:
The correct answer is d) Energy of seismic waves decreases as they travel farther from the epicenter. As distance from the epicenter increases, the energy carried by seismic waves spreads out and decreases, leading to a decrease in magnitude. This is why the damage caused by an earthquake is usually more severe closer to the epicenter and less severe farther away.
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