**Core Concept**
The nasal cavity's anatomy plays a crucial role in directing airflow during inspiration. The nasal septum, a thin wall of cartilage and bone, separates the two nasal passages and contains the septal cartilage, which is a flexible, C-shaped cartilage structure.

**Why the Correct Answer is Right**
The main current of airflow in a normal nasal cavity during inspiration is through the **inferior meatus**. This is due to the anatomical structure of the nasal passages, where the septal cartilage and the nasal conchae create a pathway that directs airflow through the inferior meatus. The inferior meatus is the lowest of the three nasal meatuses, and its size and shape allow for the majority of airflow to pass through it during inspiration.

**Why Each Wrong Option is Incorrect**
**Option A:** The superior meatus is a narrow passage that primarily contains the openings of the posterior ethmoidal air cells and the sphenoid sinus. It is not the main current of airflow during inspiration.
**Option B:** The middle meatus is a narrow passage that primarily contains the openings of the frontal, anterior ethmoidal, and maxillary sinuses. While it is an important passage, it is not the main current of airflow during inspiration.
**Option C:** The nasopharynx is the upper part of the pharynx, and it is not a specific nasal passage. It is the area where the nasal cavity merges with the oropharynx.

**Clinical Pearl / High-Yield Fact**
The nasal conchae, also known as turbinates, are long, thin bones that project into the nasal passages and help to direct airflow and humidify the air we breathe.

**Correct Answer: C. Nasopharynx.**