- A Spiracles
- B Stomata
- C Ostia
- D Nephridiopores
Correct answer: A. Spiracles
Explanation: Spiracles are small openings along the body surface of the cockroach through which air enters and leaves the tracheal respiratory system.
Concept context
The four basic animal tissue types (epithelial, connective, muscular, neural) and the cockroach as a model organism for organ-system level organisation.