Explanation : Distribution is the status of a term in regard
to extension.
The subject-term is distributed in
statements whose quantity is universal
and undistributed in statements whose
quantity is particular. The given statement is
universal as it includes 'No' with the subject
'Dog'; so, the subject is distributed
In affirmative propositions the predicate term
is always taken particularly (and
therefore undistributed) and in negative
propositions the predicate is always taken
universally (and therefore distributed). The
given statement is a negative proposition so,
the predicate 'are reptiles' is universal and
distributed.