LSAT 109 | Section 1 | Logical Reasoning: Q1

LR Question 1 Explanation

QUESTION TEXT: Marmosets are the only primates other than humans known…

QUESTION TYPE: Strengthen

CONCLUSION: Researchers hypothesize that marmosets learn to be left-handed by imitating their parents.

REASONING: No supporting evidence is given except that most marmosets are left handed.

ANALYSIS: There isn’t really an argument here, just a hypothesis. That’s fine of course. Scientists make hypotheses all of the time then try to prove or disprove them.

We can strengthen the hypothesis by showing that parents cause left handedness in some way.

___________

1. This doesn’t affect anything. We already knew that some marmosets are right handed.
2. This weakens the argument. If marmosets learn from their parents then we would expect both marmoset siblings to be either left-handed or right handed.
3. This is just interesting information. It doesn’t explain why the marmosets are ambidextrous.
4. The hypothesis is about marmosets. This answer choice tells us about humans and it entirely irrelevant. Humans were only mentioned to emphasize the rareness of left-handedness in animals. 
5. CORRECT. This does two things. First, it rules out genetics as a reason for right-handedness. These marmosets were adopted. Second, it strengthens the idea that marmosets learn by watching their parents. Here the adopted parents were right handed and so were the children.