Which of the following sets is an infinite set?
-{1, 2, 3 . . . 100}
-empty set
-the set of whole numbers less than one billion
-the set of natural numbers
-none of the above
The correct answer is option D. i.e. the set of natural numbers is an infinite set. The set of natural us infinite because it contains individually finite elements. An infinite set is a set where the number of elements are not countable.