Which term is used for numbers that identify individuals or items?

• A. Nominal numbers
• B. Rational numbers
• C. Irrational numbers
• D. Complex numbers

Answer: (A)

Nominal numbers are used to identify individuals or items. They serve as labels rather than measurements, so they don’t convey quantity or order. Think of a student ID, a product code, or a jersey number—these identifiers distinguish one item from another but aren’t meant to be counted or compared by size. In contrast, the other terms describe types of numbers used in calculations: rational numbers are fractions that can be expressed as a ratio of integers; irrational numbers cannot be written as a simple fraction; complex numbers include both a real part and an imaginary part. Those distinctions show why nominal numbers fit the idea of labeling rather than measuring or counting.