A body is executing Simple Harmonic Motion. At a displacement x its potential energy is \[{{E}_{1}}\] and at a displacement y its potential energy is \[{{E}_{2}}\]. The potential energy E at displacement \[(x+y)\] is [EAMCET 2001]

• A.            \[\sqrt{E}=\sqrt{{{E}_{1}}}-\sqrt{{{E}_{2}}}\]             
• B.            \[\sqrt{E}=\sqrt{{{E}_{1}}}+\sqrt{{{E}_{2}}}\]
• C.            \[E={{E}_{1}}+{{E}_{2}}\]
• D.            \[E={{E}_{1}}+{{E}_{2}}\]