The conductivity of semiconductor increases with increase in temperature because

Options

A. both number density of charge carriers and relaxation time increase
B. number density of charge carriers increases
C. number density of current carriers increases, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density
D. relaxation time increases

Answer

C

Explanation

number density of current carriers increase, relaxation time decreases but effect of decrease in relaxation time is much less than increase in number density.