Which statement about the number 3 is true according to number sets?

The statement that 3 is a whole number, integer, and rational number is accurate. Whole numbers are the set of non-negative numbers including zero, and integers extend this set to include negative numbers, which means that 3, as a positive whole number, fits into both categories.

Furthermore, a rational number is defined as any number that can be expressed as a fraction where both the numerator and the denominator are integers, and the denominator is not zero. In this case, 3 can be expressed as 3/1, fulfilling the criteria of a rational number. Thus, the classification of 3 as a whole number, integer, and rational number is correct and reflects its inclusion in these important number sets.