Two perfectly identical wires are in unison. When the tension in one wire is increased by 1%, then on sounding them together 3 beats are heard in 2 sec. The initial frequency of each wire is : [Pb. PET 2002]

• A. \[220{{s}^{-1}}\]
• B. \[320{{s}^{-1}}\]
• C. \[150{{s}^{-1}}\]
• D. \[300{{s}^{-1}}\]