Refer to the Figure

Refer to the figure. Which organism is an aquatic invertebrate that lacks a specialized respiratory system, and how does it compensate for this?

A) A, only; its body is flattened and thin.
B) B, only; water enters through numerous pores and passes into water canals
C) C, only; its feathery external gills provide a large surface area for gas exchange
D) Both A and B; A has a flattened thin body and B brings water through numerous pores into water channels
E) A, B and C; A has a flattened thin body, B brings water through numerous pores into water channels, and C has feathery external gills providing a large surface area for gas exchange.