Which of the following diode is reverse biased

Which of the following diodes is reverse biased?

Which of the following diodes is forward biased ?

Which of the following is reverse biased diode?

Which of the following diodes is forward-biased ?

Which of the following diodes is forward biases?

In which one of the following devices the reverse biased characteristics of a p-n junction diode are used?

In the following, which one of the diodes is reverse biased ?