Question

complete the statement below. the respiratory system is divided into...
...the relevant and irrelevant respiratory systems.
...the upper and lower respiratory systems.
...the right and left respiratory systems.
...the major and minor respiratory systems.

Explanation:

In anatomy, the respiratory system is commonly divided into upper (nose, pharynx, larynx) and lower (trachea, bronchi, lungs) parts.

Answer:

B. ...the upper and lower respiratory systems.