Insect in which all the ten pairs of spiracles are open and functional is known as:

Correct option is B

In insects, spiracles are external openings of the tracheal respiratory system. Most insects have ten pairs of spiracles— 2 thoracic (1 pair each on the meso- and metathorax) and 8 abdominal (on the first eight abdominal segments).
When all 10 spiracles are open and functional, the insect is said to have a holopneustic type of tracheal system.
�� Types of Tracheal Systems Based on Spiracle Functionality:
1. Holopneustic ✅
· All 10 pairs of spiracles (2 thoracic + 8 abdominal) are open and functional.
· Common in most larvae and adult terrestrial insects (e.g., grasshoppers, caterpillars).
2. Apneustic ❌
· No functional spiracles.
· Found in aquatic insects (e.g., some aquatic larvae) that rely on cutaneous respiration or gills.
3. Propneustic ❌
· Only one pair of spiracles (usually anterior thoracic) is functional.
· Seen in early instar larvae of some flies (e.g., mosquito larvae).
4. Metapneustic ❌
· Only the last pair (posterior abdominal) of spiracles is functional.
· Seen in late-instar larvae of Diptera (e.g., house fly maggots).