Assertion: Action spectrum of photosynthesis is much broader than the absorption spectrum of chlorophyll a.
Reason: Accessory pigments with different absorption spectra are also present in chloroplasts.

a. Both assertion and reason are true and the reason is the correct explanation of the assertion.
b. Both assertion and reason but the reason is the correct explanation of the assertion.
c. Assertion is true but reason is false.
d. Both assertion and reason are false.