Answer
Option (D)
Work Step by Step
The numbers $-1, -2, -3, ...$ are negative integers.
If the number 0 is included, then:
The numbers $0, 1, 2, 3...$ are nonpositive integers, for while 0 is not negative, it is also not positive like the rest of the numbers.
Thus, the given set is the set of nonpositive integers.
The answer is Option (D).
