The gas `A_(2)` in the left flask allowed to react with gas `B_(2)` present in right flask as `A_(2)(g)+B_(2)(g)hArr2AB(g),K_(c)=4` at `27^(@)C.` What is the concentration of AB when equilibrium is established ?
A. 1.33 M
B. 0.66 M
C. 0.33 M
D. 2.66 M