Two masses \[{{m}_{1}}\] and \[{{m}_{2}}\] are attached to a string which passes over a frictionless smooth pulley. When \[{{m}_{1}}=10kg,\] \[{{m}_{2}}=6kg,\,\]the acceleration of masses is [Orissa JEE 2002]

• A.             20 \[m/{{s}^{2}}\]
• B.             \[5m/{{s}^{2}}\]
• C.             2.5 \[m/{{s}^{2}}\]
• D. \[10m/{{s}^{2}}\]