Whoever murdered Jansen

Answer choices

1. A

   Out of Scope - Term Shift5% picked this

   If there had been footprints at the scene of the crime, the police would

   With Herbert the rule states that if he had committed the murder, the police would have found either his fingerprints or his footprints. So for him the question of leaving fingerprints or footprints but the police not finding them isn’t a possibility. For Samantha, she would have avoided leaving fingerprints or footprints in the first place, so again the question isn’t a possibility.

   5%
2. B

   Out of Scope4% picked this

   Jansen's office was the scene of

   The conditions are such that determining who murdered Jansen does not require knowing anything about where the murder occurred.

   4%
3. C

   Correct62% picked this

   No one but Herbert and Samantha was in Jansen's office on the day

   Why this is right

   This makes Herbert and O → H or S Samantha the only people who could have killed Jansen, so when the argument rules Herbert, it can be inferred that it was Samantha who was the murderer.

   Skill tested: Sufficient Assumption · how this choice captures the argument's function is the move to repeat next time.

   62%
4. D

   Weakens17% picked this

   The fingerprints found at the scene of the crime were

   The fingerprints found could not have been Samantha’s. And they were not Herbert’s. So if they were not Jansen’s, the investigation should probably include another suspect.

   17%
5. E

   Inference12% picked this

   The fingerprints found at the scene of the crime were

   If each claim in the argument S → FI + FO were true, then Samantha did S not leave any fingerprints or ჻ FI + FO footprints. So the fingerprints found by the police could not have been hers.

   12%