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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) . Assertion (A) : Emission of electrons in photoelectric effect can be suppressed by applying a sufficiently negative electron potential to the photoemissive substance. Reason (R) : A negative electric potential, which stops the emission of electrons from the surface of a photoemissive substance, varies linearly with frequency of incident radiation. In the light of the above statements, choose the most appropriate answer from the options given below:

1. (A) is false but (R) is true.
2. (A) is true but (R) is false.
3. Both (A) and (R) are true and (R) is the correct explanation of (A) .
4. Both (A) and (R) are true but (R) is not the correct explanation of (A) .

Correct answer: Both (A) and (R) are true but (R) is not the correct explanation of (A) .

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