What are counting numbers starting from 1 and increasing called?

• A. Whole numbers
• B. Integers
• C. Natural numbers
• D. Rational numbers

Answer: (C)

The term for counting numbers that start from 1 and increase is "natural numbers." Natural numbers include the set {1, 2, 3, 4, ...} and are used for counting and ordering. They represent quantities and are foundational in both mathematics and everyday counting scenarios.

Whole numbers, on the other hand, include all natural numbers plus zero, forming the set {0, 1, 2, 3, ...}. Integers encompass all whole numbers as well as negative numbers, resulting in the set {..., -3, -2, -1, 0, 1, 2, 3, ...}. Rational numbers consist of all numbers that can be expressed as a fraction where both the numerator and denominator are integers, including both positive and negative numbers, as well as zero.

Thus, the correct identification of counting numbers that begin from 1 and continue upwards is found in the definition of natural numbers.