What is the best classification for 0.5?

A. integer, rational number, real number

B. whole number, integer, real number

C. rational number, real number

D. irrational number, real number

The best definition for 0.5 is C, rational number, real number.

0.5 is a rational number because it can be expressed as a ratio, a/b, with b not equal to 0 (0.5 = 1/2). 0.5 is a real number because it's a rational number and all rational numbers are real.