Astronomer: Most Stars are Born in Groups of Thousands, Each Star in a Group Forming from the Same Parent Cloud of Gas.

QUESTION: Astronomer: Most stars are born in groups of thousands, each star in a group forming from the same parent cloud of gas. Each cloud has a unique homogeneous chemical composition. Therefore whenever two stars have the same chemical composition as each other, they must have originated from the same cloud of gas.

Which of the following, if true, would most strengthen the astronomer's argument?

(A) In some groups of stars, not every star originated from the same parent cloud of gas.
(B) Clouds of gas of similar or identical chemical composition may be remote from each other.
(C) Whenever a star forms, it inherits the chemical composition of its parent cloud of gas.
(D) Many stars in vastly different parts of the universe are quite similar in their chemical compositions.
(E) Astronomers can at least sometimes precisely determine whether a star has the same chemical composition as its parent cloud of gas.

Astronomer: Most stars are born in groups of thousands, each star in a group forming from the same parent cloud of gas- is a GMAT Critical question. This particular GMAT Critical Reasoning topic has been taken from the book ‘GMAT Official Guide verbal review ’. This particular topic is the Assumption and conclusion type of question. For this type, the candidates need to provide an assumption which supports the conclusion provided in the passage. GMAT critical reasoning tests the logical and analytical skills of the candidates. Critical reasoning in GMAT requires candidates to find the strengths and weaknesses of the argument, or find the logical flaw in the argument. The GMAT CR section contains 10 -13 GMAT critical reasoning questions out of 36 GMAT verbal questions.

ANSWER: C
EXPLANATION: The GMAT Critical Reasoning tests a competitor's cognitive, logical, and scientific reasoning skills. The applicant must justify the right option by following the same right statement and removing irrelevant arguments.

To resolve this problem of the Ascension, we must separate the dispute. The next sentence contains a proposition (must), so this is a decision and the main necessity is a reason.

Now let us check the option one by one:

1. In some groups of stars, not every star originated from the same parent cloud of gas.
   Incorrect
   This argument is similar to the first one. The idea is an assumption of the same part of cloudiness of gas, but this time it's with substance signatures assembled. However, this isn't what the proposal involves. In reality, they need to be assembled with like substance signatures to start with. If they don't have a comparative substance signature, then how would they have anything like this? Something that's opposed to what the claim states next time out of extent.
2. Clouds of gas of similar or identical chemical composition may be remote from each other.
   Incorrect
   The decision doesn't cover the reality that clouds of gas of same or similar chemical composition could be remote from each other. In this incident, the request is whether the stars have started from a comparable fog of gas or not - we are not stressed over the distance between these surges of gas - bypass this decision. Ultimately, this choice doesn't uphold the end in any way.
3. Whenever a star forms, it inherits the chemical composition of its parent cloud of gas.
   Correct
   The clouds of gas and dust that eventually become stars come together in a special way: the gas particles are so close together that they can escape each other's repulsive forces pretty easily. The individual atoms of their constituent elements are so close together that they form a solid, impenetrable object. They may get tangled up in this way, forming a cloud around our solar system. In some cases, gravity pulls gas and dust together into larger clumps. The gravitational attraction of these clumps increases as they grow larger; when they get big enough that the gravitational potential energy is high enough to start out nuclear fusion reactions in their cores, stars like our sun appear."
4. Many stars in vastly different parts of the universe are quite similar in their chemical compositions.
   Incorrect
   It's an intriguing definition but not one that guides us towards the answer in this case. Astronomers have defined chemically identical stars as those that are the same size and temperature, with similar chemical compositions (in terms of their elements) and the same brightness and temperature. Stars aren't machines so their chemical elements don't come from the same dust-poor nebula; different parts of the nebulae can come from different supernovas or even different galaxies. Of course, it's possible that two stars could come from nebulae which were relatively nearby to each other, allowing them to trace influences.
5. Astronomers can at least sometimes precisely determine whether a star has the same chemical composition as its parent cloud of gas.
   Incorrect
   Astronomers are able to determine what the chemical composition of a star is. They do this by observing the light that travels out from a star, which contains many different elements of different types, such as hydrogen and helium vapour. Because light travels at a fixed speed, its wavelength can be measured over time to determine its colour. Then the colour can be used to determine the element composition. This unique method allows us to measure precisely whether or not a star has the same composition as its original gas cloud.

Suggested GMAT Critical Reasoning Questions

•  Seeking a competitive advantage, some professional service firms
• A new medication for migraine seems effective, but there is concern that the medication might exacerbate heart disease.
• JIT stands for Just-In-Time. More than a standardized methodology or systematic process, it is a philosophy
• A major network news organization experienced a drop in viewership in the week
• Between 1980 and 2000 the sea otter population of the Aleutian Islands declined precipitously.
• Because no employee wants to be associated with bad news in the eyes of a superior
• Until recently most astronomers believed that the space between the galaxies in our universe was a near-perfect vacuum
• The Extremely High Cost of Running a World Class Zoo is Limiting
• Few of the corporate contributions to the earthquake relief fund, aside from Pterocom
• The Marison County Police Department recently implemented a new traffic safety program
• French cuisine is highly regarded all over the world.
• Politician: Tourists don't visit our city because of its reputation of high crime.
• Critics have Long been Puzzled by the Inner Contradictions of Major Characters in John Webster’s Tragedies.
• A person reading a new book for pleasure is like a tourist traveling to a new place.
• But man is not destined to vanish. He can be killed, but he cannot be destroyed, because his soul is deathless and his spirit is irrepressible.
• The pioneers of the teaching of science imagined that its introduction into education would remove the conventionality, artificiality, and backward-lookingness
• Josh has twenty years of typing experience behind him
• If the books have been cataloged last week, why haven’t they been placed on the shelf?
• According to a survey of graduating medical students conducted by Association of American Medical College
• People's television-viewing habits could be monitored by having television sets.