How does the author support his argument that people depend on the continued existence of coral reefs? A) by quoting experts and scientists who believe that humans cannot survive without the existence of coral reefs B) by claiming that human beings have a religious and social obligation to not harm, but encourage the growth of coral reefs C) by detailing science experiment results that showed conclusively that humans will be adversely affected if all coral reefs disappeared D) by asserting that the reefs contain many plants and animals used in medicines, chemicals, or other products that humans need to lead healthy lives