The material used for solar cell should have a band gap:

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: Photodiodes are preferably operated in reverse bias condition for light intensity measurement.
Reason $R$: The current in the forward bias is more than the current in the reverse bias for a $p-n$ junction diode.
In the light of the above statements,choose the correct answer from the options given below:

What kind of $p-n$ junction diode does not require any kind of bias?

$A$ photodiode is fabricated from a semiconductor with a bandgap of $2.5 \ eV$. Can it detect a wavelength of $6000 \ \mathring{A}$?

The energy gap of an $LED$ is $2.4 eV$. When the $LED$ is switched $ON$,the momentum of the emitted photons is

Which one of the following symbols represents a photodiode?