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Evolution: Extinction Rates


99.9% of all species that have ever existed on planet Earth are now extinct.

Which of the following statements BEST explains this fact?


Climate changes associated with large comet or asteroid impacts occur faster than organisms can change themselves and adapt to the new environmental conditions.


Genetic variations within a population occur through random mutations, and given enough time, the environment will change in such a way that no existing genetic-based phenotypes permit survival.


The accumulation of random mutations in the genome of all organisms eventually leads to frameshift mutations in critical genes and are ultimately lethal.


The rapid increase in global temperatures in the past 100 years, combined with ocean acidification, heavy metal contamination, and ozone depletion caused by human activities have caused 99.9% of all of Earth's species to go extinct.