Equivalence relation requires:
AJust reflexive
BREFLEXIVE + SYMMETRIC + TRANSITIVE
CJust transitive
DAnti-symmetric
Answer & Solution
Correct answer: B. REFLEXIVE + SYMMETRIC + TRANSITIVE
Equivalence relation: aRa (reflexive), aRb ⇒ bRa (symmetric), aRb ∧ bRc ⇒ aRc (transitive). Partitions set into disjoint equivalence classes. e.g., 'congruence mod n', 'same age'.
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