Answer: A) Whole number
Step-by-step explanation:
The set of whole numbers is {0,1,2,3,...} showing that negative values are not in this set. A distance below sea level is written as a negative (where positive values are above sea level). So you won't use the set of whole numbers for this type of problem.
In contrast, something like the set of integers is {..., -3, -2, -1, 0, 1, 2, 3, ... } including negatives this time. For example, we can write -10 to indicate we're 10 feet below sea level. Rational numbers and real numbers can also be negative.