Traditional hatcheries raise fish in featureless environments and

Question

Traditional hatcheries raise fish in featureless environments and subject them to dull routines, whereas new, experimental hatcheries raise fish in visually stimulating environments with varied routines. When released into the wild, fish from the experimental hatcheries are bolder than those from traditional hatcheries in exploring new environments and trying new types of food. Fish raised in the experimental hatcheries, therefore, are more likely to survive after their release.

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

(A) It is economically feasible for hatchery operators to expose fish to greater visual stimulation and to more varied routines.
(B) The quality of the environments into which hatchery-raised fish are released has little effect on the fish’s survival rate.
(C) At least some fish raised in traditional hatcheries die because they are timid in their foraging for food.
(D) Hatchery-raised fish that are released into the wild do not eat many different types of food.
(E) No fish in the wild lives in visually stimulating environments.

Rickooreoisb · Answer

Question Type:
Necessary Assumption

Stimulus Breakdown:
Conclusion: fish raised in the experimental hatcheries are more likely to survive after release. Premises: the experimental hatcheries expose fish to more visual stimulation and varied routines as compared to traditional hatcheries. When released, fish from experimental hatcheries are bolder in exploring new environments and trying new foods.

Answer Anticipation:
There's a big gap here between being bolder and being more likely to survive. We can predict either a bridge assumption that links the two concepts (fish that are bolder are more likely to survive) or a defender assumption that defends against an objection to this link up (going into new environments and eating new foods doesn't make fish more likely to die).

Correct answer:
C

Answer choice analysis:
(A) This is a classic trap answer for Necessary Assumption questions. The economic feasibility of a course of action is almost never necessary to assume. Consider the negation of this one: it's not economically feasible. Who cares? That just means the experimental hatcheries aren't a model for the future of commercial hatcheries.

(B) Does this have to be true in order to conclude that there's something else effecting their survival rate too (the hatchery they're from)? Nope. Eliminate.

(C) Does this one have to be true? Hard to say, maybe, so negate to be sure. What if no fish from traditional hatcheries ever die because of their foraging timidness. Well, if that's true, then how can we conclude that the fish from experimental hatcheries have a survival advantage just because they're bolder? We can't, so this negation ruins the argument, making it the correct answer.

(D) The degree of this one is troubling: "need to eat" and "many different types" make this an unlikely candidate. To see why, negate: one hatchery-raised fish can survive eating only a few types of food. Does that blow up our argument? Nope. Remember, when negating a conditional statement, just raise the possibility of a non-conforming case. If that non-conforming case doesn't ruin the argument, the answer is wrong.

(E) Another conditional, so negate with a non-conforming case! If one fish in the wild lives in a visually boring environment, does that ruin our argument? No way.

Takeaway/Pattern:
There are a lot of ways a necessary assumption can be phrased, so don't freak out if you make a solid prediction but don’t see it among the answer choices. Work wrong to right, keeping an eye out for classic traps and degree issues (A, D, and E), and stay focused on the exact task of the question. Ask yourself "does this really need to be true of the argument to work?" If the answer is no, eliminate (B). If you're not sure, negate.

Sajjad1994 · Answer

Explanation

Traditional hatcheries:  featureless environments, dull routines: fish are timid when exploring new environments or trying new foods after release.
 Experimental hatcheries:  visually stimulating, varied routines: fish are bolder in exploring and trying new foods.

Conclusion:  Fish from experimental hatcheries are more likely to survive after release.

Identify the assumption

The conclusion assumes that boldness in exploring new environments and trying new foods improves survival rates. This is not explicitly stated, maybe in the wild, boldness could be dangerous (predators, eating toxic food, etc.). So the argument assumes that boldness in these specific ways (exploring new environments, trying new food types) is advantageous for survival, not detrimental.

(A)  Economic feasibility is irrelevant to the conclusion about survival. Not required.

(B)  Quality of release environments has little effect on survival: This isn’t needed. Even if environment matters, the argument compares two hatchery types in the same release environment. The conclusion is comparative:  “more likely to survive.”  Not an assumption.

(C)  This looks good: The conclusion is that experimental-hatchery fish are more likely to survive. If no fish from traditional hatcheries die from timidity in foraging, then boldness would not explain a survival advantage. Thus, the argument assumes timidity in traditional-hatchery fish does cause some of their deaths. That’s required to conclude boldness gives a survival edge.

(D)  Hatchery-raised fish released into the wild do not eat many different types of food. Not relevant, argument is about trying new types (boldness), not how many they eat normally.

(E)  No fish in the wild lives in visually stimulating environments. Clearly false and irrelevant.

Answer: C

eaat · Answer

Argument: fish raised in experimental hatcheries are more likely to survive after release
Q: assumption required by argument 
A - doesn’t matter if it’s economically feasible or not
B - saying quality has little effect on survival rate - irrelevant 
C - yes they die, because they’re timid - sure
D - not relevant doesn’t explain why fish in experimental are more likely to survive 
E - not relevant

Traditional hatcheries raise fish in featureless environments and

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Traditional hatcheries raise fish in featureless environments and

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