Question

Platyhelminthes, like the flatworm seen here, do not have a respiratory system. All but one of the statements explains why this is possible. That is they?

A) are anaerobic organisms.
Eliminate
B) live in a moist/aquatic environment.
C) have a high surface area:volume ratio.
D) have a thin body that facilitates diffusion throughout.

Answer 1

A)

Explanation:

Platyhelminthes (notable classes cestode and trematode) live inside the specific part of the gut,from there they receive their readymade nutritive substances by the sucker/hook,so they don't need to breathe `O_2`,hence they use anaerobic respiration.