The correct option is C Mycoplasma
Mycoplasma is a genus of bacteria that are different from rest of the bacteria since they do not have cell walls.
Funaria is Bryophyte that belongs to the plant kingdom. All plants have cell walls made of cellulose.
Anabaena is a cyanobacteria which is a type of bacteria. All bacteria have cell walls made of peptidoglycan.
Mucor is a fungus. all members of fungi have cell walls made mostly of chitin.