Consider the sample space and two events A and B as is illustrated in the following figure. Choose the best option that describes the event D = A^cU B^c

S = {E1, E2, E3, E4, E5, E6, E7} is the sample space.

A = {E1, E2, E3, E5, E6}

B = {E2,E3,E4,E7}