A hydrogen atom in its first excited state ($n=2$) absorbs a photon of wavelength 100 nm and is ionised. Take $hc=1240\mathrm{eV}\mathrm{nm}$ and the ground-state ionisation energy of hydrogen as 13.6 eV. The kinetic energy of the ejected electron is

1. A$12.4\mathrm{eV}$
2. B$1.2\mathrm{eV}$
3. C$15.8\mathrm{eV}$
4. D$9.0\mathrm{eV}$