While biodiversity is indispensable to the survival of life on Earth

With regards to eliminating option D

Isn't A also explicitly stated in the argument.
In the argument it states " biodiversity does not require the survival of every currently existing species"

option A states " Biodiversity does not require that all existing species continue to exist"

Both seem same to me.

This made the rusty parts of the brain worked. Thanks for the question. Here are my two cents

The question starts off with a counter statement that even though biodiversity is indispensable to the survival of life on Earth, biodiversity does not require the survival of all the currently existing species, and then the argument goes on to provide the reasoning of why that is the case. Now one thing I noticed while going through OG explanations of CR questions is they do not all the time demarc what's the conclusion and what's the premise and rather tend to think of the argument in a structural way of what the author is trying to tell me and what reasoning it has provided(These were my two cents). So, as stated above, once you have evaluated that everything starting 'For there to be life..' is providing us the reasoning i.e. is the premise of what the author wants us to believe the conclusion is in the first part of the sentence and given it starts with counterpoint(that can't be conclusion) hence our conclusion is 'Biodiversity does not require the survival of every currently existing species'

With this, we can easily eliminate B to D as they all are the premise of the argument, while E is out of scope or rather mistaken negation, which leaves us with A

When answering this question, I relied on CR Bible techniques.
"Two types of answers typically appear in Main Point questions, and both are incorrect:
1. Answers that are true but do not encapsulate the author’s point.
2. Answers that repeat premises of the argument."

So, D is the answer that repeats the premise of the argument.

Then, I used Conclusion identification method, and mentally re-arranged the sentences in the following order:

Author presents an opposing view: For there to be life on Earth, various ecological niches must be filled;
Authors shifts back to a supporting premise: many niches, however, can be filled by more than one species;
Conclusion: biodiversity does not require the survival of every currently existing species.

Hope this helps!

"While biodiversity is indispensable to the survival of life on Earth, biodiversity does not require the survival of every currently existing species. For there to be life on Earth, various ecological niches must be filled; many niches, however, can be filled by more than one species.

Which one of the following statements most accurately expresses the conclusion drawn in the argument?

(A) Biodiversity does not require that all existing species continue to exist.
(B) There are various ecological niches that must be filled if there is to be life on Earth.
(C) The survival of life on Earth depends upon biodiversity.
(D) There are many ecological niches that can be filled by more than one species.
(E) The species most indispensable for biodiversity fill more than one ecological niche.
"

To get to the answer choice to this Must be true question, we need to find an answer choice which is true and summarises everything in the argument.
A: Summarises best
B: partially justifies
C: partially justifies
D: quotes partially
E: out of Scope

Hence, A is the answer

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