Question

At least a quarter of the World's corals have lost/ over the past 25 years and as climate change warms/ the oceans the additional carbon dioxide will make/ the water more acidic further destroying coral reefs.

• A. At least a quarter of the World's corals have lost
• B. Over the past 25 years and as climate change warms
• C. The oceans the additional carbon dioxide will make
• D. The water more acidic further destroying coral reefs
• E. No error

Answer 1

The correct option is A At least a quarter of the World's corals have lost

'A quarter has been used as a whole.
So. use has in place of 'have'
e g. Three fourths of the work has been done by me.