One approach to the question of which objects discussed by a science

One approach to the question of which objects discussed by a science are real is to designate as real all and only those entities posited by the most explanatorily powerful theory of the science. But since most scientific theories contain entities posited solely on theoretical grounds, this approach is flawed.

Argument: About response to a question about which objects discussed by science are real? The answer is "those entities posited by the most powerful theory of science".
Conclusion: Approach to consider entities real on above mentioned grounds is flawed
Reasoning: Most scientific theories contain entities posited solely on theoretical grounds

Which one of the following principles, if valid, most helps to justify the reasoning above?

Question stem: most helps to justify the reasoning above

(A) Any object that is posited by a scientific theory and that enhances the explanatory power of that theory should be designated as real. //Incorrect.. no support for posits enhancing the power of a theory in the reasoning, out of scope

(B) Objects posited for theoretical reasons only should never be designated as real. //Correct.. Says the same thing what the reasoning says

(C) A scientific theory should not posit any entity that does no enhance the explanatory power of the theory. //This option talks about basis of considering an object real or not in a theory not the other way round, doesnt help the cause.

(D) A scientific theory should sometimes posit entities on grounds other than theoretical ones. //Same as option (C)

(E) Only objects posited by explanatorily powerful theories should be designated as real. //This weakens the reasoning



Kudos if helpful

One approach to the question of which objects discussed by a science are real is to designate as real all and only those entities posited by the most explanatorily powerful theory of the science. But since most scientific theories contain entities posited solely on theoretical grounds, this approach is flawed.

Which one of the following principles, if valid, most helps to justify the reasoning above?

Now this question might seem difficult to understand due to its structure.
Premise: Approach to designate object as real in science is by explanatory powerful theory of the science.
Premise: Majority of scientific theories are theoretical.
Conclusion: Hence, this approach is flawed.

We need to find an option that validates the reasoning.
A-> Here both theories are used to designate an object as real. NO
B -> Objects posited only for theoretical reasons cannot be real. This matches with the 2nd premise, meaning it is in line with the reasoning. CONTENDER
C -> Saying this will invalidate the premise. NO
D -> This is a new reasoning and hence cannot be used NO
E -> There could be many other approaches to designate the object as real. Hence, while this option is validating the reasoning, it is not completely doing justice with the reasoning. NO

Hence answer is B


(A) Any object that is posited by a scientific theory and that enhances the explanatory power of that theory should be designated as real.
(B) Objects posited for theoretical reasons only should never be designated as real.
(C) A scientific theory should not posit any entity that does no enhance the explanatory power of the theory.
(D) A scientific theory should sometimes posit entities on grounds other than theoretical ones.
(E) Only objects posited by explanatorily powerful theories should be designated as real.

(A) Any object that is posited by a scientific theory and that enhances the explanatory power of that theory should be designated as real. - Mistaken reversal. Stem says designate as real all and only those entities posited by the most explanatory powerful theory of the science. Option says object that is posited by a scientific theory and that enhances the explanatory power of that theory should be designated as real. You see the roles are reversed?

(B) Objects posited for theoretical reasons only should never be designated as real. - Correct [This can be properly inferred from the passage]

(C) A scientific theory should not posit any entity that does no enhance the explanatory power of the theory. - Passage does not talk about an entity enhancing the explanatory power of the theory.
Passage says designate as real all and only those entities posited by the most explanatory powerful theory of the science. This again is a case of reversal.

(D) A scientific theory should sometimes posit entities on grounds other than theoretical ones. - This gives alternative recommendation.

(E) Only objects posited by explanatorily powerful theories should be designated as real. - Trap answer. Powerful theories of what? Powerful theories of science would make this option correct.­

GMATNinja

Can anyone explain me why not A ? Should be the answer of this .