Official Solution:
Lena: Single-use plastic bags should be banned in our state’s coastal towns. Over the last several years, the number of dead sea turtles found on local beaches has risen sharply. [b]This increase is probably attributable, at least in part, to plastic bag litter. The use of plastic bags by shoppers has been growing steadily.
Plastic bags often end up in the ocean, where turtles mistake them for jellyfish and ingest them.
In Lena’s argument, the two portions in boldface play which of the following roles?
[/b]
A. The first is a conclusion for which support is offered, and itself is offered to support the second; the second is the main conclusion drawn in the argument.
B. The first is a premise offered to support the second; the second is a conclusion drawn in the argument but not the main conclusion.
C. The first is a premise offered to support the only conclusion drawn in the argument; so is the second.
D. The first is the main conclusion drawn in the argument; the second is another conclusion for which support is offered, and itself is offered to support the first.
E. The first is a conclusion drawn in the argument but not the main conclusion; the second is a premise offered to support the first.
Lena’s main conclusion is that single-use plastic bags should be banned in coastal towns. To support that policy recommendation, she points to a rise in dead sea turtles and to increasing plastic-bag use.
The first boldface statement:
“This increase is probably attributable, at least in part, to plastic bag litter” is not the main conclusion. It is an intermediate conclusion: Lena is inferring a causal link between plastic bags and turtle deaths.
The second boldface statement:
“Plastic bags often end up in the ocean, where turtles mistake them for jellyfish and ingest them” is a premise that provides a mechanism explaining how plastic bags could cause turtle deaths, thus supporting the intermediate causal conclusion.
(A) Incorrect. The second boldface is not the main conclusion; the main conclusion is the call to ban bags.
(B) Incorrect. The second boldface is not a conclusion; it is support.
(C) Incorrect. The first boldface is not a premise; it’s an inference.
(D) Incorrect. The first boldface is not the main conclusion.
(E) Correct. The first boldface is a conclusion drawn in the argument but not the main conclusion; the second boldface is a premise offered to support the first.
Answer: E