The ionization energy of a hydrogen-like Bohr atom is 4 Rydbergs. Find the wavelength of radiation emitted when the electron jumps from the first excited state to the ground state: [1 Rydberg \[=2.2\times {{10}^{-18}},h=6.6\times {{10}^{-34}}Js,\] \[c=3\times {{10}^{8}}m/s\]. Bohr radius of hydrogen atom \[=5\times {{10}^{-11}}m\]

• A.  \[400\overset{\text{o}}{\mathop{\text{A}}}\,\]
• B.  \[300\overset{\text{o}}{\mathop{\text{A}}}\,\]
• C.  \[500\overset{\text{o}}{\mathop{\text{A}}}\,\]
• D.  \[600\overset{\text{o}}{\mathop{\text{A}}}\,\]