The energy of a photon in a monochromatic light of wavelength $621 \ nm$ matches with the band gap of a semiconducting material. Then the minimum energy required to create an electron-hole pair from the semiconductor is
[Take $hc = 1242 \ eV-nm$,where $h$ is Planck's constant and $c$ is speed of light in vacuum] (in $eV$)

• A
  $3.4$
• B
  $1.7$
• C
  $2$
• D
  $2.2$