Sets a = {1,2,3}, b= {3,1,2}, c = {3,2,2,1}. Are these sets equal? (Is a=b=c)? Explain your answer.

a) Yes, they are equal.
b) No, a ≠ b ≠ c.
c) a is equal to b but not to c.
d) b is equal to c but not to a.