Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Koehler illumination is designed to produce bright and uniform illumination.
Reason (R): It is a lighting system in which the condenser focuses the image of the light source directly onto the specimen plane.
In the light of the above statements, choose the most appropriate answer from the options given below :