Subsets of {1,2,3} with even size

JEE Main medium Year: 2020 Maths
Select all subsets of ({1,2,3}) with even cardinality.
Options
  1. ∅
  2. {1}
  3. {1,2}
  4. {1,3}
  5. {2,3}
Answer
∅, {1,2}, {1,3}, {2,3}
Solution
Count sizes 0 or 2.