Coral reefs are one of the most _____________ , biologically complex, and diverse marine ecosystems on Earth. This ecosystem is one of the _____________ paradoxes of the biosphere: how do clear, and thus nutrient-poor, waters support such _____________ and productive communities?

A

common, sensitive, fruitful

B

fragile, fascinating, prolific

C

deep, strange, exuberant

D

frail, unrecognised, wealthy