Four linear elastic springs are connected to mass ‘M’ as shown in Figure. The natural frequency of the system is

• A. \(\frac{{\left( {\sqrt {\frac{{4{\rm{k}}}}{{3{\rm{m}}}}} } \right)}}{{\left( {2{\rm{\pi }}} \right)}}\)
• B. \(\frac{{\left( {\sqrt {\frac{{4{\rm{k}}}}{{\rm{m}}}} } \right)}}{{\left( {2{\rm{\pi }}} \right)}}\)
• C. \(\frac{{\left( {\sqrt {\frac{{\rm{k}}}{{4{\rm{m}}}}} } \right)}}{{\left( {2{\rm{\pi }}} \right)}}\)
• D. \(\frac{{\left( {\sqrt {\frac{{3{\rm{k}}}}{{4{\rm{m}}}}} } \right)}}{{\left( {2{\rm{\pi }}} \right)}}\)