Pheretima does not exhibit sexual dimorphism as there is no phenotypic difference between males and females of the same species.
The Musca or the housefly shows complete metamorphosis. It is the phenomenon in which the organism passes through all the four stages of the life cycle. The four distinct stages are as the egg, larval or maggot, pupal and adult stages. The adult lays the fertilized eggs and the egg hatches to form the larvae. The larvae develop into a pupa and then the pupa is transformed to adult.
Chameleon exhibits the change of their skin colouration and pattern through a combination of various colours.
Taenia does not exhibit polymorphism.
So, the correct answer is option B.