LSAT Explanation PT 38, S1, Q24: One-year-olds ordinarily prefer the taste of

LSAT Question Stem

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

Logical Reasoning Question Type

This is a Necessary Assumption question. 

Correct Answer

The correct answer to this question is A. 

LSAT Question Complete Explanation

First, let's analyze the argument in the passage. The passage states that one-year-olds typically prefer sweet food to salty food. However, if they are fed salty food for a year, they will develop a taste for it and choose salty food over sweet food. The conclusion is that a young child's taste preferences can be affected by the type of food they are exposed to. The premises are the observations about one-year-olds' initial preferences and the change in preferences after being fed salty food.

An "Evaluate" question for this argument could be: "Is there any other factor that could cause the change in taste preferences between ages one and two?"

Now, let's discuss the question type and answer choices. This is a Necessary Assumption question, which means we need to identify the assumption required by the argument.

a) Two-year-olds do not naturally prefer salty food to sweet food.

This is the correct answer. If two-year-olds naturally prefer salty food, then the change in preferences could be explained by their natural development, rather than the exposure to salty food. By assuming that two-year-olds do not naturally prefer salty food, the argument can conclude that exposure to salty food affects taste preferences.

b) A child's taste preferences usually change between age one and age two.

This answer choice is not necessary for the argument. Even if taste preferences don't usually change between ages one and two, the argument is still valid as it's based on the specific case of feeding salty food to the child.

c) Two-year-olds do not naturally dislike salty food so much that they would not choose it over some other foods.

This answer choice is not necessary for the argument. It's actually the opposite of what we want. If two-year-olds naturally dislike salty food, then the fact that they're choosing it must mean something has caused that effect.

d) The salty food fed to infants in order to change their taste preferences must taste pleasant.

This answer choice is irrelevant. The argument is about whether exposure to salty food affects taste preferences, not whether the salty food must taste pleasant.

e) Sweet food is better for infant development than is salty food.

This answer choice is also irrelevant. The argument is about the effect of exposure to salty food on taste preferences, not about which type of food is better for infant development.

In summary, the correct answer is A, as it is the necessary assumption required by the argument. The argument assumes that two-year-olds do not naturally prefer salty food to sweet food, which allows it to conclude that exposure to salty food affects taste preferences.