Query about Question 4 from "PrepSwift Quant Tickbox Quiz #1 (Arithmetic Column 1)" [6351]

https://prepswift.gregmat.com/quizzes/quiz/prepswift-quant-tickbox-quiz-1-arithmetic-column-1 (Question 4)


Isn’t 0 neither positive nor negative? Why in the solution have we considered 0 in the list of smallest non-negative integers?

not positive does not necessarily mean negative (and vice-versa).