Chemistry · Structure of atom

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Isotopes of an element show identical chemical behavior. Reason (R): Chemical properties are dictated by the number of electrons, which depend on the nuclear proton count. In the light of the above statements, choose the correct answer from the options given below:

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