Answer:
The addition of a chromosome in an egg cell.
Explanation:
Mutation may be defined as sudden, heritable change in the DNA sequences. The mutation may be caused during the DNA replication or may be caused by the environmental factors.
The mutation that occurs in the gametic cells may pass down from parents to their offspring. The addition of an extra chromosome in egg cell will be inherited in the next generation.
Thus, the correct answer is option (C).
