It has been hypothesized that our solar system was formed from a cloud

Question

It has been hypothesized that our solar system was formed from a cloud of gas and dust produced by a supernova- an especially powerful explosion of a star. Supernovas produce the isotope iron-60, so if this hypothesis were correct, then iron-60 would have been present in the early history of the solar system. But researchers have found no iron-60 in meteorites that formed early in the solar system's history, thereby disproving the hypothesis.

Which one of the following is an assumption required by the argument?

(A) If a meteorite is formed early in the solar system's history, it contains chemical elements that are unlikely to be found in gas and dust produced by a supernova.
(B) Other solar systems are not formed from clouds of gas and dust produced by supennovas.
(C) Supernovas do not produce significant quantities of any form of iron other than iron-60.
(D) Researchers have found iron-60 in meteorites that were fanned relatively late in the solar system's history.
(E) If there had been iron-60 present in the early history of the solar system, it would be found in meteorites formed early in the solar system's history.

LSAT

saswata4s · Answer

Hypothesis: Supernovas produce the isotope iron-60.

If this hypothesis were correct, then iron-60 would have been present in the early history of the solar system. 
But researchers have found no iron-60 in meteorites that formed early in the solar system's history and disproved the hypothesis.

Unstated assumption by researchers: If there was iron-60 present in the early days, it did not disintegrate over time.

Ans E.

Srid · Answer

Can anyone explain why c is not answer

Su1206 · Answer

This is an assumption question. Thus, we need to find an answer that  'Author believes to be true'.  It's ok if that is not true in real world; If author shall believe in it, it is an assumption.

(C) Supernovas do not produce significant quantities of any form of iron other than iron-60. - Author need not believe this to be true. It can be true that Supernovas do produce significant quantities of other forms of Iron, but, if iron-60 exists in meteors, it is sufficient to prove the hypothesis.

So, C is not necessary assumption.

Lets take a look at E : 
 (E) If there had been iron-60 present in the early history of the solar system, it would be found in meteorites formed early in the solar system's history. -  For author to believe his reasoning to be true, he needs to believe in this statement.   
   By negating E, we weaken the argument.

Hope this helps.

If you like my explanation, do upvote. It motivates me. 
  Su!

napolean92728 · Answer

The  correct answer is (E)  If there had been iron-60 present in the early history of the solar system, it would be found in meteorites formed early in the solar system's history.

Reasoning:
 In the argument, the hypothesis is that the solar system was formed from a cloud of gas and dust produced by a supernova, which would have included iron-60. The researchers have found no iron-60 in meteorites that formed early in the solar system's history, and the conclusion is that this disproves the hypothesis.
For this argument to hold, an important assumption must be that if iron-60 were indeed present in the early history of the solar system, it would have been incorporated into meteorites formed during that early period. This is exactly what answer (E) suggests — that the absence of iron-60 in early meteorites indicates its absence in the early solar system. If iron-60 had been present, it would have been found in these meteorites.

Why the other options are wrong:
(A)  If a meteorite is formed early in the solar system's history, it contains chemical elements that are unlikely to be found in gas and dust produced by a supernova.
This statement is unrelated to the argument. The argument is not about whether the elements in the meteorite could be found in the supernova's gas and dust, but about whether iron-60 should have been present if the supernova hypothesis is true.

(B)  Other solar systems are not formed from clouds of gas and dust produced by supernovas.
This is not an assumption required by the argument. The argument is focused on our own solar system, not others. It doesn’t rely on what happens in other solar systems.

(C)  Supernovas do not produce significant quantities of any form of iron other than iron-60.
This is irrelevant because the argument doesn't require us to rule out the production of other forms of iron. It only focuses on whether iron-60 was present in the early solar system, not on the total quantity or forms of iron produced by supernovas.

(D)  Researchers have found iron-60 in meteorites that were formed relatively late in the solar system's history.
This is not relevant to the argument. The researchers are concerned with the absence of iron-60 in meteorites that formed early in the solar system’s history, and this answer choice would not address that absence.

It has been hypothesized that our solar system was formed from a cloud

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It has been hypothesized that our solar system was formed from a cloud

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615 to 715 in 15 Days (Ria's Strategies)

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