I request some expert to give views on this question : though I agree with E option as correct answer.
Present perfect tense is needed, also option B distorts the original meaning. It states that of the 99% of 5 million different species have disappeared. There could be possibility of having greater number of different species. Whereas, original question states that of the 5 million different 99% have disappeared. This is a definitive quantity.
To keep the meaning intact I will go for option E.
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Present perfect tense is needed, also option B distorts the original meaning. It states that of the 99% of 5 million different species have disappeared. There could be possibility of having greater number of different species. Whereas, original question states that of the 5 million different 99% have disappeared. This is a definitive quantity.
To keep the meaning intact I will go for option E.
...
