The correct option for this question is upper
esophageal sphincter.
The rest all options serves as the common passage for air and
food particles.
The route of Air which we inspire is as follows:
- Nostrils
- Nasal cavity
- Pharynx
- Larynx (glottis is a part of larynx)
- Trachea
- Primary bronchi
- Secondary bronchi
- Tertiary bronchi
- Bronchioles
- Alveoli
Alveoli is the site where exchange of gas takes place.
