If $${\text{P}}\left( {\text{A}} \right) = {\text{P}}\left( {\text{B}} \right) = \frac{1}{3}$$     and $${\text{P}}\left( {{\text{A}} \cap {\text{B}}} \right) = \frac{1}{6}$$   . Then, the value of $${\text{P}}\left( {{\text{A}} \cup {\text{B}}} \right)$$   will be

A. $$\frac{2}{3}$$

B. $$\frac{1}{{18}}$$

C. 1

D. $$\frac{1}{2}$$

Answer: Option D