Conditioning of inspiratory air occurs in .............

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the conditioning of inspiratory air occurs. Conditioning refers to the modifications that the air undergoes before it reaches the lungs.

2. **Identifying the Role of the Respiratory System**: The respiratory system is responsible for facilitating gas exchange, which primarily occurs in the lungs. However, before air reaches the lungs, it must be conditioned.

3. **Recognizing the Components of the Respiratory Tract**: The respiratory tract includes structures such as the nostrils, nasal passages, pharynx, larynx, trachea, bronchi, and bronchioles. Each of these plays a role in conducting air to the lungs.

...