The correct options are
A E1∩E2 = ϕ
C E1∪E2 ∪...∪ En = S
D P(Ei) > 0 for all i = 1, 2, ⋯, n
A set of events
E1, E2, ..., En is said to represent a partition of the sample space S if
Ei∩Ej = ϕ, i≠j, i, j = 1, 2,…, n
E1∪E2∪...∪En = S
and
P(Ei) > 0 for all i = 1, 2, . . ., n