Q5

[lhermary]

Where does it say D?

Thanks

[ManhattanPrepLSAT1]

Great question! There are two places one can point to in the passage that would support answer choice (D).

Lines 30-31 suggest that several proposals have been put forward. the definition of several sometimes states "3 or more" and sometimes states "more than one."

Lines 59-61 uses the plural form for both "theories that rest on extraterrestrial intervention" and "theories like the first." If there are theories like the first, then there are at least 3 theories; the first theory, the second theory, and theories like the first.

Incorrect Answers

(A) is unsupported. The second theory is more controversial (line 39) than the first, but that does not imply the two theories have divided the scientific community.
(B) is unsupported. The author uses the ability of the two theories to account for frequency variation in the process of assessing them. But they were not formulated in order to explain the frequency of polarity reversal.
(C) is unsupported. The author does investigate the two theories to some extent, but we cannot say they have been "extensively investigated.
(E) is unsupported. No indication has been provided for when these theories were introduced.

[taaron]

Two questions:

1) How does the LSAT usually treat the word "several"??

I chose C rather than D because I understood the use of the plural "theories" to refer to such theories in general as opposed to theories regarding this particular phenomenon - for example, the author generally has a problem with theories that depend on extraterrestrial intervention (such as dinosaur extinction in Q2).

2) How can I avoid mistakes like this in the future?

Thank you!

[ManhattanPrepLSAT1]

This one was tough for me to find an explanation I felt really comfortable with, so don't be hard on yourself for your initial interpretation.

My first thought was along your first question, how many is "several?" The answer for the LSAT is more than one. So that by itself is not able to ensure that there are more than just the two explanations discussed in the passage. However, if you go back to lines 59-61 and read very carefully, they don't just say theories that depend on extraterrestrial intervention and theories that don't. They say theories that depend on extraterrestrial intervention, and theories like the first, "which account for the phenomenon solely by means of the thermodynamic state of the outer core..."

This means that there must be more than one theory in the latter category that account for for the phenomenon of polarity reversal. Why? Because one theory accounts for such a phenomenon. Two or more theories account for such a phenomenon. The plurality of the language is what allows one to infer that there are other theories out there that seek to explain the phenomenon.

2) How can I avoid mistakes like this in the future?

This is not something you'll face frequently on the LSAT. It's much more important to know the meaning of terms that imply "some" and terms that imply "most."

Such as these:

[episcopoandrew]

I'm noticing a pattern between this question and preptest 54, passage 3, question 18 about the cakewalk and the use of singular and plural in the passage. My takeaway is whenever the passage uses plural or singular, and the ACs to a question like this appear mentioning more than two theories, look back to the passage to find if the passage uses singular or plural. It's very easy to forget in the midst of a passage if it talks about theories or the one interpretation as opposed to several interpretations.