LSAT 111 – Section 1 – Question 16

LSAT 111 - Section 1 - Question 16

October 2001

You need a full course to see this video. Enroll now and get started in less than a minute.

Request new explanation

Target time: 1:14

This is question data from the 7Sage LSAT Scorer. You can score your LSATs, track your results, and analyze your performance with pretty charts and vital statistics - all with a Free Account ← sign up in less than 10 seconds

Question
QuickView		 Type Tags Answer
Choices		 Curve Question
Difficulty		 Psg/Game/S
Difficulty		 Explanation
PT111 S1 Q16
+LR
Main conclusion or main point +MC
Causal Reasoning +CausR
Eliminating Options +ElimOpt
A
8%
160
B
0%
155
C
85%
165
D
2%
160
E
4%
158
128
141
155
 +Easier 147.471 +SubsectionMedium

Kevin’s explanation

You need a full course to see this video. Enroll now and get started in less than a minute.

On the basis of the available evidence, Antarctica has generally been thought to have been covered by ice for at least the past 14 million years. Recently, however, three-million-year-old fossils of a kind previously found only in ocean-floor sediments were discovered under the ice sheet covering central Antarctica. About three million years ago, therefore, the Antarctic ice sheet must temporarily have melted. After all, either severe climatic warming or volcanic activity in Antarctica’s mountains could have melted the ice sheet, thus raising sea levels and submerging the continent.

Summarize Argument: Counter-Position
New evidence shows that the Antarctic ice sheet has melted at least once in the last 14 million years. The author does not state this outright, but leads us to this conclusion by explaining that ocean fossils dating back only three million years have been found under Antarctica’s current ice sheet. We also get an explanation for how this could have happened: climate activity or volcanoes could have melted the ice, leading to ocean conditions that would explain the fossils. And of course, if the ice melted three million years ago, it can’t have been solid for 14 million years.

Identify Conclusion
The author’s conclusion, which is not explicitly stated, is that Antarctica’s ice sheet has not been in place for all of the last 14 million years (implied by the claim that the ice temporarily melted three million years ago).

A
Antarctica is no longer generally thought to have been covered by ice for the past 14 million years.
The author never actually tells us how this new discovery has affected general thinking. We don’t know if this new knowledge is widespread yet, and popular opinion can be slow to change.
B
It is not the case that ancient fossils of the kind recently found in Antarctica are found only in ocean-floor sediments.
This is not stated in the argument. In fact, the author’s reasoning relies on assuming the opposite: that these fossils are from ocean creatures, thereby supporting the idea that the Antarctic ice melted into an ocean long ago.
C
The ice sheet covering Antarctica has not been continuously present throughout the past 14 million years.
This is a fair paraphrase of the conclusion implied by the author. All the evidence is used to establish that the Antarctic ice melted three million years ago, which in turn rebuts the previously-held belief that the ice hadn’t melted for 14 million years.
D
What caused Antarctica to be submerged under the sea was the melting of the ice sheet that had previously covered the continent.
Like (E), this is used to support the plausibility of Antarctica’s ice having melted three million years ago. Because it supports another claim, this can’t be the main conclusion.
E
The ice sheet covering Antarctica was melted either as a result of volcanic activity in Antarctica’s mountains or as a result of severe climatic warming.
Like (D), this is used to support the plausibility of Antarctica’s ice having melted three million years ago. Warming and volcanoes also aren’t given as the only options, but rather just as possible causes of melting.

Take PrepTest

Review Results

LSAT PrepTest 111 Explanations

Section 1 - Logical Reasoning

Section 2 - Reading Comprehension

Section 3 - Logical Reasoning

Section 4 - Logical Reasoning

Get full LSAT course

Leave a Reply