Which of the following is a subset of {1,2,3}?

Question

Answers are 

a. {0}

b.{0,1}

c. {1,2,3}

d.{1,2,3,4}

Answer 1

{1,2,3}  However, the empty set is also a subset, Ø.

{0} is a set with one element, the number 0. So, it is not a subset of your given set.