D. would be the correct answer because a "whole" number is one without decimals. Whole numbers are NOT negative, so any number 0 and above without a decimal place is a whole number.
When rounding, take decimal places that are 5 or greater and make them 10. You can think of it as adding 1 to the number to the left of the rounded decimal place.
ex. 1.5 rounds up to 2
the 5 becomes a 10 which turns the 1 into a 2
ex. 5.6 rounds to 6
the 6 rounds up to 10 making the 5 a 6
ex. 9.2 rounds to 9
because 2 is less than five it rounds down to 0
