Two masses \[{{m}_{1}}\] and \[{{m}_{2}}\] are suspended together by a massless spring of constant k. When the masses are in equilibrium, \[{{m}_{1}}\] is removed without disturbing the system. Then the angular frequency of oscillation of \[{{m}_{2}}\] is

• A. \[\sqrt{\frac{k}{{{m}_{1}}}}\]
• B. \[\sqrt{\frac{k}{{{m}_{2}}}}\]
• C. \[\sqrt{\frac{k}{{{m}_{1}}+{{m}_{2}}}}\]
• D. \[\sqrt{\frac{k}{{{m}_{1}}{{m}_{2}}}}\]