On increasing the reverse bias to a large value in p-n junction diode then value of current  ​
a) remain fixed
b) increase slowly
c) decrease slowly
d) suddenly increase
Kindly explain  

Dear Student , 
On increasing the in the reverse bias to a large value in the p-n junction diode then the value of current will suddenly increase .It happens due to increasing the reverse voltage above a certain voltage level which exceeds the breakdown voltage and the p-n diode breaks down and then the current through the p-n increases rapidly which is known as the reverse current .
Regards