Assertion (A): Reversal of the polarity of the membrane generates an action potential.
Reason (R): Membranes are positive on the outer surface at the resting stage.
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.