The major premise backing up the author’s conclusion is that dating a student, regardless of legal age of consent, is unethical for any professor.
Based on this piece of evidence (which we accept as a factual premise) the author makes a value claim by saying “professors SHOULD Not date their students.”
1 way to strengthen an argument’s conclusion is to bring an unstated assumption to light. By explicitly stating the assumption, this adds an explicit fact that will strengthen the claim.
Following the author’s line of reasoning, he or she is essentially saying that because this activity is unethical, any professor should not engage in the activity.
The author, in making his value claim (i.e, should), must be necessarily assuming that if an activity is unethical, then a professor should NOT engage in it.
If it were true that a professor can engage in any activity, ethical or unethical, then this entire value argument about what the professor “should” do completely falls apart.
Answer B brings the assumption to light by making it an explicit premise. By providing info. that says “professors should act in an ethical manner,” the answer choice bolsters the author’s claim that professor SHOULD not engage in this one particular unethical activity: dating students.
In this way answer B is correct.
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