Critical Reasoning

“If the forest continues to disappear at its present pace, the koala will approach extinction,” said the biologist.
“So all that is needed to save the koala is to stop deforestation,” said the politician.
Which one of the following statements is consistent with the biologist’s claim but not with the politician’s claim?
(A) Deforestation continues and the koala becomes extinct.
(B) Deforestation is stopped and the koala becomes extinct.
(C) Reforestation begins and the koala survives.
(D) Deforestation is slowed and the koala survives.
(E) Deforestation is slowed and the koala approaches extinction.

Only B implies that there might be another reason (other than deforestation) that could drive koala to extinction. This is consistent with the biologists' claim but not with the politicians'.

Aaah.. Now I see it... thanks.. OA is B

Why cant the answer to this be D?

Please explain.

Thanks.