LSAT Explanation PT 42, S4, Q1: Many newborn babies have a yellowish

LSAT Question Stem

Which one of the following, if true, most helps to support the position of the second group of doctors? 

Logical Reasoning Question Type

This is a Strengthen question. 

Correct Answer

The correct answer to this question is D. 

LSAT Question Complete Explanation

Let's first break down the argument in the passage and identify its structure. There are two groups of doctors with opposing views on treating newborns with high levels of bilirubin:

Argument (1):

Premise: High levels of bilirubin might cause tetanus if it enters the brain of newborns.

Conclusion: Newborns should be treated to reduce bilirubin levels.

Argument (2):

Premise: The brain's natural defenses normally prevent bilirubin from entering.

Conclusion: It's not necessary to treat newborns to reduce bilirubin levels.

The question type is Strengthen, and we are asked to find an answer choice that supports the position of the second group of doctors (those who argue against treating newborns to reduce bilirubin levels).

An "Evaluate" question for this argument could be: "Does bilirubin have any positive effects on the health of newborns?"

Now, let's examine each answer choice:

a) The treatment that most effectively reduces high levels of bilirubin in newborns has no known negative side effects.

- This answer choice strengthens the argument in favor of treatment (Argument 1), so it does not support the second group of doctors.

b) Some diseases that occur in newborns can weaken the brain's natural defenses and allow bilirubin to enter.

- This answer choice also strengthens the argument in favor of treatment (Argument 1), as it suggests that the brain's natural defenses might not always be effective in preventing bilirubin from entering the brain.

c) In newborns, the pigment bilirubin, like other pigments, occurs not only in the blood but also in fluids involved in digestion.

- This answer choice does not directly support either argument, as it only provides additional information about where bilirubin can be found in newborns.

d) Bilirubin neutralizes certain potentially damaging substances to which newborns are exposed at birth.

- This is the correct answer choice. It supports the position of the second group of doctors by suggesting that high levels of bilirubin could have a positive effect on the health of newborns.

e) Among doctors who recommend treating newborns to reduce high levels of bilirubin, there is general agreement about what levels should be considered excessively high.

- This answer choice strengthens the argument in favor of treatment (Argument 1) by suggesting that there is a consensus among doctors on when to treat high bilirubin levels. It does not support the position of the second group of doctors.