A
It is a contention that the argument purports to show is the main point of disagreement between the two groups of critics mentioned.
B
It is cited as a commonly accepted reason for accepting a hypothesis for which the argument offers independent evidence.
C
It is a claim whose acceptance by critics who differ on other issues is cited by the argument as evidence of its truth.
D
It is a claim about the nature of art that according to the argument accounts for disputes that only appear to concern the aesthetic merits of certain types of paintings.
E
It is a claim whose acceptance by both of the two disputing parties is cited as evidence for a conclusion the argument draws about the disagreement.
A
Several major pharmaceutical companies in the region have been secretly dumping large amounts of waste into the ocean for many years.
B
A new strain of bacteria is attacking P-plankton by destroying their cell walls and is attacking the respiratory systems of fish species X, Y, and Z.
C
A powerful toxin in the water is killing off P-plankton by inhibiting their production of a chemical they use in reproduction.
D
Fish species X, Y, and Z are all experiencing widespread starvation within the affected region, and the loss of P-plankton is driving their death rates up even higher.
E
Global warming has changed the climatic conditions of the ocean all along the northeast coast of the country.
Nightbird is an unsigned painting that some attribute to the celebrated artist Larocque. Experts agree that it was painted in a style indistinguishable from that of Larocque and that if it was not painted by Larocque, it was undoubtedly painted by one of his students. A recent analysis showed that the painting contains orpiment, a pigment never yet found in a work attributed to Larocque. Therefore, the painting must have been done by one of Larocque’s students.
Summarize Argument
The author concludes that Nightbird must have been painted by one of Larocque’s students. He supports this by noting that experts agree that the painting is both in Larocque’s style and was either painted by him or by one of his students. He also points out that the painting contains orpiment, a pigment never found in a painting attributed to Larocque.
Notable Assumptions
The author assumes that the orpiment in Nightbird means it wasn’t painted by Larocque, just because none of his known paintings use the pigment. However, Larocque could have used orpiment in a painting not yet attributed to him. Based on this assumption, the author then assumes that the orpiment in Nightbird must mean it was painted by one of his students.
A
Few of Larocque’s students ever used painting techniques that differed from Larocque’s.
Since few of his students used painting techniques that differed from Larocque’s, and Nightbird “was painted in a style indistinguishable from that of Larocque,” (A) strengthens the conclusion that Nightbird was painted by one of Larocque’s students.
B
Larocque never signed any of his paintings.
The fact that Larocque never signed any of his paintings does not weaken the conclusion that Nightbird was painted by one of his students. Perhaps his students never signed their paintings either.
C
No painting currently recognized as the work of one of Larocque’s students contains orpiment.
The key reason for concluding that Nightbird was painted by a student of Larocque was the orpiment, which paintings attributed to Larocque don’t have. But if none of his students’ paintings contain orpiment either, why should we still conclude that it was painted by one of them?
D
None of Larocque’s students is considered to be an important artist.
The importance of Larocque’s students has nothing to do with the conclusion that one of his students painted Nightbird. As far as we know, an unimportant artist could have painted Nightbird just as easily as an important one.
E
The use of orpiment became more popular in the years after Larocque’s death.
Just because orpiment was more popular after Larocque’s death doesn’t mean that it didn’t exist or that he didn’t use it before his death. It also doesn’t mean that his students, many of whom presumably outlived him, could not also have used orpiment after well after his death.