One end of a spring of force constant \[k\] is fixed to a vertical wall and the other to a body of mass \[m\] resting on a smooth horizontal surface. There is another wall at a distance \[{{x}_{0}}\] from the body. The spring is then compressed by 3\[{{x}_{0}}\] and released. The time taken to strike the wall from the instant of release is (given\[{{\sin }^{-1}}(1/3)=(\pi /9))\]

• A. \[\frac{\pi }{6}\sqrt{\frac{m}{k}}\]        
• B. \[\frac{2\pi }{3}\sqrt{\frac{m}{k}}\]
• C. \[\frac{\pi }{4}\sqrt{\frac{m}{k}}\]        
• D. \[\frac{11\pi }{9}\sqrt{\frac{m}{k}}\]