Proposition: No teacher is on time for the class. Which conclusion follows?

ANo person who is on time for classes is a teacher ✓ Correct

BSome teachers are not late for their classes

CMost teachers come to their classes on time

DFew teachers come on time for their classes

Correct answer: (A) No person who is on time for classes is a teacher

Explanation

The valid inference is that no one who is on time for classes is a teacher.

'No teacher is on time' is a universal negative proposition.

A universal negative converts fully, its subject and predicate simply swapping.

So 'no teacher is on time' yields 'no one on time is a teacher'.

This conversion preserves the exclusion between the two classes.

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