The built-in potential of a p-n junction diode is $0.7 \mathrm{~V}$. If the diode is forward biased and the applied voltage is 0.3 $\mathrm{V}$, the effective barrier height is

• A

  $0.7 \mathrm{~V}$
• B

  $0.3 \mathrm{~V}$
• Correct answer
  C

  $0.4 \mathrm{~V}$
• D

  $1 \mathrm{~V}$

Hence, the correct answer is option: 'C'.