Consider the following statements concerning flame cells of flatworms and identify the correct answer choice. I. They help in osmoregulation and excretion. II. Protonephridium has excretory pores. III. Waste products are excreted with the help of cilia present on the cell lining.

 Flame cells are ciliated cells that are part of the excretory and osmoregulatory system of Platyhelminthes. This system, known as a protonephridium, consists of branching tubules that open to the exterior through excretory pores. Flame cells occur at the ends of the tubules, into which their cilia project. Fluid, containing water and nitrogenous waste products, diffuse into the flame cells and is directed through the tubules to the exterior by movements of the cilia, which resemble the flickering of flames.

----------------------------------------------------------------------------------