The correct option is C Autotomy
Autolysis is the self-digestion or the destruction of a cell through the action of its own enzymes.
Autophagy is an intracellular degradation system the delivers cytoplasmic constituents to the lysosome.
Autogamy is the self-fertilization.
Autotomy, also called as self-amputation is the behaviour whereby an animal sheds or discards its one or more of its own appendages, usually as a self-defense mechanism. Arm autotomy in asteroids is same as that of tail autotomy in vertebrates, typically occurs when the animal is attacked and appears to facilitate escape.
Therefore, the correct answer is option C.