Answer: set.
- A set
- B sequence
- C function
- D relation
Correct answer: A. set
Explanation: A set is a well-defined collection of distinct objects.
A Venn diagram makes set identities visual: A∪B is everything inside either circle, A∩B is only the overlap, and the region outside both circles represents the complement of their union - directly illustrating De Morgan's law (A∪B)′ = A′∩B′.
Concept context
Types of sets, operations (union/intersection/complement), relations, and types of functions with domain and range