Blood gills are found in

Answer: Option D

Blood gills are found in Chironomids and Trichopterans.
A blood gill is a gill like structure restricted to organs with spacious lumen and poorly developed/absent trachea, found in larvae of aquatic insects.
The functionality of this gill to respiration, and concludes it exists more likely to absorb water.
Thin plates or filaments with a copious tracheal supply and only a very small blood cavity, structures which are typically developed in such insects as Trichoptera.