SAT Inferences Question

The End-Triassic mass extinction happened approximately 201 million years ago, when about 80 percent of species (including many species of bivalves) died off. Researchers have proposed the effects of a sudden release of carbon dioxide as one mechanism that may have brought on this mass extinction. But mass extinctions, while abrupt in geological terms, unfold over thousands or millions of years: it's likely that multiple factors drove widespread species loss. Based on the text, the author would most likely agree with which statement about the End-Triassic mass extinction?