PrepTest 103, Section 2, Question 20
Martha's friend, who is very knowledgeable about edible(48 more words not shown)
Which one of the following(12 more words not shown)
- AJeanne is a(17 more words not shown)
- BRolfe belongs to(19 more words not shown)
- CSome of Noriko's(28 more words not shown)
- DMost of Leon's(24 more words not shown)
- EMany of Teresa's(23 more words not shown)
Reading the argument
Which chrysanthemums are edible and pleasant to eat? They might not be the daisies. Martha's friend says no daisies qualify. Martha points out that some daisies are chrysanthemums and that some chrysanthemums do qualify. But those could be different members of the chrysanthemum group. We have not been told that the edible, palatable ones include any daisies.
Knowing that some mammals are eaten does not establish the same thing about every kind of mammal. Cows and other animals can share that broad category without sharing every property. Membership in a category does not transfer one member's characteristics to another.
What we’re looking for
For the parallel flaw, look for two groups that each overlap a third group, followed by an unsupported claim that they overlap each other. Here, the daisy group and the edible-and-palatable group each contain chrysanthemums. Martha assumes at least one flower falls in both of those two groups.
Working the answers
- A
The chorus's reputation is a property of the group as a whole. Jeanne belongs to the group, so the argument gives her individual excellence without establishing it. A renowned chorus might contain a weak singer.
That is different from Martha's two-overlapping-groups mistake. We would need some chorus members in one group, some in another, and an unsupported conclusion that the two sets share a member. A instead moves from the whole chorus to one singer.
- B
The word “all” supplies the connection Martha lacks. Every member of the reading group is an avid reader, and Rolfe belongs to it, so Rolfe must be an avid reader. If every chrysanthemum were edible and palatable, the daisies known to be chrysanthemums would qualify. But Martha only tells us that some chrysanthemums qualify.
- CCorrect
The debate team matches the chrysanthemum group. Noriko's sisters match the daisies, and poor students match the edible, palatable flowers. Some sisters are on the team, and some poor students are on the team. That does not establish that any of the sisters are among the poor students.
The sisters could all be excellent students while different teammates have poor academic records. Both premises would be true and the conclusion false. Likewise, the edible chrysanthemums could be different flowers from the chrysanthemums that are daisies.
- D
Good swimmers are said to be quite strong, and most of Leon's friends are good swimmers. The strength property therefore applies to those swimming friends. This supports the limited conclusion about at least some friends being strong.
There is no gap between two merely partial overlaps. The swimmer-to-strong rule covers the entire swimmer group, unlike Martha's claim that only some chrysanthemums have the desired property.
- E
Writing a book about good writing does not establish being a good writer. Someone could discuss the subject badly. E confuses the subject of the books with the skill of their authors.
It does not identify two groups that each overlap a third group and then assume they overlap. Its unsupported connection is between a book's topic and its author's ability, rather than the group-membership connection Martha mishandles.
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