Scientists claim that the discovery of the first

[bestdudearound]

This question is from Old Paper based tests.

[deleted because problem is from a banned source - see below]

I selected C but the correct answer is E. Can you please explain what is wrong with C and how does E correct that mistake?

[Willy]

This question is from Old Paper based tests.

[deleted because problem is from a banned source - see below]

I selected C but the correct answer is E. Can you please explain what is wrong with C and how does E correct that mistake?

Lets place Option C in the statement,

Scientists claim that the discovery of the first authenticated mammal bones in amber could provide important clues to determine how mammals colonized the islands of the West Indies and when they did

If I split it at the parallel structure.

Discovery could provide clues to determine how mammals colonized the islands of the West Indies

AND

Discovery could provide clues to determine when they did. "colonized" is understood after "did" but it is wrong construction i.e. we need 1st form of verb after "did".

Also, I think THEY in the option C is ambiguous.

[tim]

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