Which statement is true about rational numbers?

Rational numbers are defined as numbers that can be expressed as a ratio of two integers, where the denominator is not zero. This definition encompasses a wide range of numbers, including fractions, integers, and finite or repeating decimals. Since rational numbers can be written in the form ( \frac{a}{b} ), where ( a ) and ( b ) are integers and ( b \neq 0 ), option B accurately captures the essence of what defines a rational number. This understanding is fundamental in mathematics and underscores the vastness of the set of rational numbers, including numbers like ( \frac{1}{2}, -\frac{3}{4}, 0, ) and ( 5 ) (which can be written as ( \frac{5}{1} )).

The focus on their expressibility as a ratio of two integers is critical, as it differentiates them from irrational numbers, which cannot be expressed in this way.