In the open ocean, a shark will catch almost any small fish it decides

Question

In the open ocean, a shark will catch almost any small fish it decides to attack. The best chance a small fish has, once it is spotted by a hungry shark, it that the shark will promptly find something else to attack. Therefore, one of the benefits gained by small fish that swim in large groups known as schools is a reduced chance of being attacked by a shark.

Which one of the following statements is an assumption on which the author’s argument depends?

(A) Sharks live primarily on a diet of small fish.

(B) Sharks do not eat an entire school of fish at one time.

(C) The sheer number of fish in a school prevents sharks from attacking.

(D) Sharks are the main danger to small fish in the open ocean.

(E) Small fish are able to sense when they are being spotted by sharks.

VikasReddyK · Answer

Conclusion: Swimming in schools is safer for small fish, because there is high chance that other small fish might distract a shark's attention.

(A) Sharks live primarily on a diet of small fish.
-- It is said in the argument that shark will catch almost anything. So this assumption is not necessary. Eliminate A.
(B) Sharks do not eat an entire school of fish at one time.
** If sharks do eat entire school at once, then small fish's chance of survival goes does by being part of a large group. So this assumption is necessary. Keep B.
(C) The sheer number of fish in a school prevents sharks from attacking.
-- Argument only talks about the distracting shark and not threatening shark with large numbers. For the conclusion made with given premises this assumption is not needed. Eliminate C.
(D) Sharks are the main danger to small fish in the open ocean.
-- Sharks catch almost anything is already given and this statement doesn't add anything relevant to arrive at the given conclusion. Eliminate D.
(E) Small fish are able to sense when they are being spotted by sharks.
-- If they can spot and escape, then the conclusion doesn't matter. If they can spot and not escape, then it doesn't explain anything extra needed to arrive at the conclusion. Eliminate E.

Answer: B

NiftyNiffler · Answer

The answer should be B. In the first go, A, C and D are extreme or irrelevant and thus can be eliminated. Negation of A breaks the conclusion, i.e., if the school gets eaten all at once then small fishes gain no advantage by being part of a school.

E speaks of small fishes' escape strategy which is a classic trap answer.

E speaks of small fishes' escape strategy which is a classic trap answer.

A_Nishith · Answer

The argument states that small fish swimming in schools have a reduced chance of being attacked by a shark because the shark might find something else to attack.  The assumption required for this argument is that sharks do not attack entire schools of fish at once, which supports the idea that being in a school reduces the individual fish's chance of being attacked.

Let's evaluate the options:

(A) Sharks live primarily on a diet of small fish.
This may be true, but it does not directly relate to the mechanism by which being in a school reduces the risk of attack.

(B) Sharks do not eat an entire school of fish at one time.
This is a necessary assumption for the argument. If sharks attacked entire schools, being in a school would not reduce the individual fish's chances of being attacked.

(C) The sheer number of fish in a school prevents sharks from attacking.
This suggests a different mechanism (intimidation by numbers) than the one presented in the argument, which focuses on distraction.

(D) Sharks are the main danger to small fish in the open ocean.
While this might be relevant, it is not essential to the argument about how being in a school reduces the chance of attack by a shark.

(E) Small fish are able to sense when they are being spotted by sharks.
This is not related to the argument's focus on the shark's behavior and does not impact the reasoning about schools reducing attack risk.

Correct Answer: (B)

In the open ocean, a shark will catch almost any small fish it decides

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In the open ocean, a shark will catch almost any small fish it decides

Prep Toolkit

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

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My Rewards