Which of the following statements is not correct in the case of light emitting diodes?

The following graph represents:

$A$ $p-n$ photodiode is made of a material with a band gap of $2.0\, eV$. The minimum frequency of the radiation that can be absorbed by the material is nearly:

An $LED$ (Light Emitting Diode) is constructed from a $p-n$ junction based on a certain $Ga-As-P$ semiconducting material whose energy gap is $1.9\, eV$. What is the wavelength of the emitted light?

$A$ $p-n$ photodiode is fabricated from a semiconductor with a band gap of $2.8 \; eV$. Can it detect a wavelength of $6000 \; nm$?

For $LED$s to emit light in the visible region of the electromagnetic spectrum,they should have an energy band gap in the range of: