If A is any event associated with sample space and if E\textsubscript{1}, E\textsubscript{2}, E\textsubscript{3} are mutually exclusive and exhaustive events. Then which of the following are true?
(A) $P(A) = P(E_1)P(E_1|A) + P(E_2)P(E_2|A) + P(E_3)P(E_3|A)$
(B) $P(A) = P(A|E_1)P(E_1) + P(A|E_2)P(E_2) + P(A|E_3)P(E_3)$
(C) $P(E_i|A) = \frac{P(A|E_i)P(E_i){\sum_{j=1}^{3} P(A|E_j)P(E_j)}, i=1,2,3$}
(D) $P(A|E_i) = \frac{P(E_i|A)P(E_i){\sum_{j=1}^{3} P(E_i|A)P(E_j)}, i=1,2,3$}
Choose the correct answer from the options given below: