Answer: The correct answer is Option 2.
Explanation:
Natural transmutation is defined as the decay process of the radioactive elements which occur spontaneously by a process that causes transmutation.
Artificial transmutation is defined as the process where artificially induced nuclear reaction is done by the bombardment of nucleus with high energy particles on a radioactive element. It is a spontaneous reaction.
Natural decay or radioactive decay are the processes in which a nucleus disintegrates spontaneously on its own. There are many processes by which this decay takes place.
Hence, the correct answer is Option 2.
