What is the set of natural numbers denoted as?

The set of natural numbers is typically denoted by the letter N, and its representation as {1, 2, 3, 4, 5, 6, ...} indicates that it includes all positive integers starting from 1 and continuing indefinitely. This definition aligns with the most commonly accepted convention in mathematics, particularly when focusing on the set of natural numbers that do not include zero.

In contrast, other options represent different sets of numbers: the set W usually represents whole numbers, which include zero along with the natural numbers, while Z denotes the set of integers that includes both positive and negative whole numbers as well as zero. The set M, though less standard, seems to include natural numbers along with zero, which generally isn't recognized as part of natural numbers under traditional definitions. Thus, identifying the correct representation of natural numbers as the first choice is a clear reflection of mathematical convention.