Final answer:
The nose warms and humidifies the inspired air, which is important for preventing lung and trachea damage caused by cold, dry air. It also filters particulate matter from the air, providing additional protection to the respiratory system.
Step-by-step explanation:
The nose plays a crucial role in normal airway humidification and the correct answer to the question is B. It warms and humidifies the inspired air. The nasal cavity functions to warm the air to body temperature and add moisture from the mucous membranes as air is inhaled. This is vital as it helps to equilibrate the air to the body conditions, which is important for preventing damage that could be caused by inhaling cold, dry air. Additionally, the nasal cavity filters particulate matter from the air using cilia and mucus. This process of warming and humidifying air, along with filtering, acts as a protective mechanism for the respiratory system, reducing risks of lung infection and damage to the trachea and lungs.