Question: Construct a relation on the set {a, b, c, d} that is
a) reflexive, symmetric, but not transitive.
b) irreflexive, symmetric, and transitive.
c) irreflexive, antisymmetric, and not transitive.
d) reflexive, neither symmetric nor antisymmetric, and transitive.
e) neither reflexive, irreflexive, symmetric, antisymmetric, nor transitive.