Read the sentence to find out whether there is any grammatical or idiomatic error in it. The error, if any, will be in one part of the sentence. The corresponding letter of that part is the answer. If the given sentence is correct as it is, then choose option ‘No Error’ as the answer response. (Ignore errors of punctuation, if any).

The research paper investigates (A)/ how climate change, destructive fishing practices, (B)/ and overexploitation (C)/ have created a vicious circle in the ecosystem. (D)

Correct option is E

The given sentence is error-free.
The sentence discusses an investigation into the interconnected effects of climate change, destructive fishing practices, and overexploitation. Specifically, it explores how these factors have initiated a harmful cycle of consequences or events in the ecosystem.