Assertion: Generally heavy nuclei are unstable.
Reason: It has more neutrons and protons.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false
B.
If both assertion and reason are true but reason is not the correct explanation of assertion.
In heavy nuclei, the repulsive forces between the protons are more effective the nuclear attractive forces and these forces reduce the stability of the nucleus.