One major biotic factor that affects the health of coral reefs is/are a) hurricanes. b) symbiotic algae 0) water pollution d) extreme temperatures

The answer is: B. symbiotic algae

A biotic factors refers to the influence that given by living organisms. Symbiotic algae affect the health of coral reefs because algae produce oxygen and help the coral reefs in their waste removal. In return, the coral reefs provide protection and important substances for the algae.