A.A∪B=B∪A,A∩B=B∩A
B.A∪(B∪C)=(A∪B)∪C,A∩(B∩C)=(A∩B)∩C
C.A∪(B∩C)=(A∪B)∩(A∪C),A∩(B∪C)=(A∩B)∪(A∩C)
D.A∪B=A∩B,A∩B=A∪B