The displacement x of a particle along a straight line at time t is given by: \[\text{x = }{{\text{a}}_{\text{0}}}\text{+}\frac{{{\text{a}}_{\text{1}}}\text{t}}{\text{2}}\text{+}\frac{{{\text{a}}_{\text{2}}}}{\text{3}}{{\text{t}}^{\text{2}}}\]. The acceleration of the particle is

• A. \[\frac{{{a}_{2}}}{3}\]
• B. \[\frac{2{{a}_{2}}}{3}\]
• C. \[\frac{{{a}_{1}}}{2}\]
• D. \[{{a}_{0}}+\frac{{{a}_{2}}}{3}\]