Write Einstein's photoelectric equation, state clearly the three salient features observed in the photoelectric effect which can be explained on the basis of the above equation.

a) E = hν - φ, Features: Threshold frequency, Intensity dependence, Instant

aneous emission
b) E = hν + φ, Features: Threshold frequency, Intensity dependence, Time delay
c) E = hν - φ, Features: Photoelectric current, Stopping potential, Frequency independence
d) E = hν + φ, Features: Photoelectric current, Stopping potential, Threshold frequency