Assumption—CE. The correct answer choice is (B)
While it is often the case in Supporter assumption questions that the correct answer choice will link together a premise to “rogue” information that appears for the first time in the conclusion, this stimulus is a reminder that the Supporter answer choice can also link two previously unconnected premises.
The first sentence presents a recent study into gum disease, which showed that people who address problems quickly and directly are significantly less likely to have gum disease than are people who react to problems by refusing to think about them. This result is evidence of a correlation between refusing to think about problems and an increased probability of having gum disease.
The second sentence introduces a causal relationship, that stress can have a negative effect on the immune system. In the conclusion, this “negative effect” is referred to as “suppression of the immune system.” Borrowing this phrasing from the conclusion, the relation created by this premise is:
S = stress
SIS = suppression of immune system
- C E
The argument then concludes that “the study’s results clearly indicate that some forms of gum disease are caused or aggravated by suppression of the immune system.” This is a causal conclusion, diagrammed as:
GD = some forms of gum disease
- C E
The logical gap here is that the conclusion explicitly cites the study’s results as support, but the study did not mention anything about suppression of the immune system. So, your prephrase is that the correct answer choice will provide the link between refusing to think about your problems and suppression of the immune system. Given the causal relationship between stress and suppression of immune system already present in the second sentence, the correct answer choice will likely say that refusing to think about your problems causes stress, creating this causal chain:
RTAP = refusing to think about problems
- C E/C E/C E
RTAP S SIS GD
Answer choice (A): This answer choice reverses the causal chain contemplated by the stimulus. Here, it is a painful condition, apparently a reference to gum disease, that causes a person not to address problems quickly and directly.
Answer choice (B): This is the correct answer choice. As discussed above, this information provides a causal link that is required for the conclusion to be valid, that refusing to think about something troubling increases a person’s level of stress, which then suppresses the immune system, causing or aggravating gum disease.
Answer choice (C): Although this answer choice relates to stress and dealing with problems quickly, terms important to the prephrase, it is incorrect, because it presents them in an order that is not required for the conclusion to be valid. This is an example of a Shell Game answer choice. In the stimulus, failing to deal with problems quickly and directly produced stress. Here, however, those who are under stress deal with problems quickly and directly.
Answer choice (D): This is an attractive answer choice, because it describes a common sense outcome that explains the correlation between quick, direct problem solving and gum disease better than the conclusion reached by the argument. However, it is the conclusion actually reached in the stimulus that is the focus of the question, and this answer choice is irrelevant to that conclusion.
Answer choice (E): This answer choice provides a causal relationship that explains why some people refuse to think about problems. However, this explanation is not necessary to understand the connection between refusing to think about problems, for whatever reason, and the incidence of gum disease.