A photocell is lit by extremely faint light above its threshold frequency, and a current starts to flow at once. Read the Assertion (A) and Reason (R) and choose the correct option.

• Assertion (A): Photoelectrons appear with no measurable delay, even when the light is very dim.
• Reason (R): Light energy arrives in discrete photons, and a single photon can give its whole energy hν to one electron at once.