Fairly straight forward question. Answer, D.
a) John never takes a vacation of more than one week in length.- We don't care about how long his vacations are. The question talks about his schedule last week and we know he wasn't on vacation then. So out.
b) Every day last week that John worked, he worked for an entire workday. -Out of scope. Even on normal days we don't know if he works full-time or part-time, so negating this would in no way change the conclusion
C) John does not take vacations
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a) John never takes a vacation of more than one week in length.- We don't care about how long his vacations are. The question talks about his schedule last week and we know he wasn't on vacation then. So out.
b) Every day last week that John worked, he worked for an entire workday. -Out of scope. Even on normal days we don't know if he works full-time or part-time, so negating this would in no way change the conclusion
C) John does not take vacations
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