Mechanisms of breathing vary among different groups of animals depending mainly on their habitats and levels of organization, which option contain all correct statements?

(i) Lower invertebrates like sponges, coelenterates, flatworms, etc., exchange O 2 with CO 2 by simple diffusion over their entire body surface.

(ii) Earthworms use their moist cuticle for exchange O 2 with CO 2 .

(iii) Insects has tracheal tubes to transport atmospheric air within the body.

(iv) Special vascularized structures called gills are used by most of the aquatic arthropods and molluscs.

(v) Terrestrial forms use vascularized bags called lungs for the exchange of gases.

(vi) Among vertebrates, fishes use gills whereas reptiles, birds and mammals respire through lungs and also use skin for respiration.