The amplitude of velocity of a particle is given by, \[{{V}_{m}}={{V}_{0}}/(a{{\omega }^{2}}-b\omega +c)\] where \[{{V}_{0}}\], a, b and c are positive: The condition for a single resonant frequency is

• A. \[{{b}^{2}}<4ac\]
• B. \[{{b}^{2}}=4ac\]
• C. \[{{b}^{2}}=5ac\]
• D. \[{{b}^{2}}=7ac\]