If D = {1, 2}, which of the following is NOT a subset of D?

If D = {1, 2}, which of the following is NOT a subset of D?

Step 1: Understand what a subset is. A subset is a set that contains some or all elements from another set.
Step 2: Identify the original set D. In this case, D = {1, 2}.
Step 3: List the elements of D. The elements are 1 and 2.
Step 4: Check the options given to see if they are subsets of D.
Step 5: Determine if the set {3} contains any elements from D. It does not, because 3 is not in {1, 2}.
Step 6: Conclude that {3} is NOT a subset of D because it contains an element that is not in D.

Subset Definition – A subset is a set that contains only elements from another set.
Empty Set – The empty set is a subset of every set.