Q. The inclusion of sets into R = {{1, 2}, {1, 2, 3}, {1, 3, 5}, {1, 2, 4}, {1, 2, 3, 4, 5}} is necessary and sufficient to make R a complete lattice under the partial order defined by set containment. (Solved)
1. {1}, {2, 4}
2. {1}, {1, 2, 3}
3. {1}
4. {1}, {1, 3}, {1, 2, 3, 4}, {1, 2, 3, 5}
- c. {1}