The correct option is B Musca - Complete metamorphosis
Musca is a genus of flies. It includes Musca domestica (the common housefly). Houseflies undergo complete metamorphosis consisting of an egg, larva or maggot, pupa, and adult stage.
Pheretima is not sexually dimorphic they are hermaphroditic, an individual in which reproductive organs of both sexes are present.
Chameleon exhibits camouflage and not mimicry. Though mimicry and camouflage are similar, Mimicry is where an animal is trying to look like something else that is obvious but uninteresting or undesirable, while camouflage is an animal trying to blend in with its surroundings and not appear obvious.
Taenia is a genus of tapeworms. Polymorphism is an appearance of forms or "morphs" differing in color and number of attributes within a single species. And this cannot be seen in tapeworms but can be seen in insect order Lepidoptera(which include butterflies).