Consider the following statements: 1. The radiation falling on a photodiode is primarily a minority carrier injector. 2. The short-circuit current of a reverse biased photodiode under illumination varies exponentially with light intensity. 3. The photo voltage emf of an open-circuited photodiode varies logarithmically with the light generated short-circuit current. 4. The spectral response of a photodiode does not depend upon the frequency of the incident light. Which of these statements are correct?

Answer: Option D