Which statement best summarizes "Save the Coral Reefs”? Coral reefs are a very important component of the ocean’s ecosystem because they support sea life, such as crabs and sea turtles. In fact, over four thousand species depend on the survival of the reefs, which are being destroyed by bleaching. More must be done immediately to save the reefs.

Coral reefs are a very important component of the ocean's ecosystem because they support sea life, such as crabs and sea turtles. In fact, over four thousand species depend on the survival of the reefs, which are being destroyed by bleaching. More must be done immediately to save the reefs.

Explanation:

Coral reefs are among the world's most complex habitats, home to thousands, or even millions of marine species. Around one-third of all species of marine fish spend a majority of their lives on coral reefs.  Coral reefs worldwide are steadily decreasing and endangered by a number of factors including pollution, climate change, fishing, and human activities. Unless nothing is attempted to save them, then by the end of the century many coral reefs will no longer survive as functional ecosystems. Via strong protection measures and efficient coral reef resource management, people can reduce some of the risks to reefs posed by local human activities.

taking into account that a theme is the central topic a text treats and can be developed through a story, play, poem etc. the following are themes that can be further developed:  

my best friend jeffrey has many unusual interests. (the story could be about each of the unususal interests)

once a man gives his soul over to evil, he can never go back. (this could be a saying or a proverb)

the three sheepdogs lay around the yard all day. (it could be developed detailing how each of these sheepdogs lay around)

a priest's collar has an unusual effect upon people. (it could be developed detailing the different effect upon people)

innocence is a powerful force in a world full of corruption. (it could be developed detailing how is a world full of corruption)

king lear is a play shakespeare wrote later. (it is just a sentence and doesnt give any idea or topic to be discussed in details.

evil often wears the disguise of innocence. (this could be a saying or a proverb)