**Core Concept**
The ethmoidal sinus is one of the paranasal sinuses that communicate with the nasal cavity, and its innervation plays a crucial role in the transmission of pain sensations from the affected area.

**Why the Correct Answer is Right**
The ethmoidal sinus is innervated by the anterior and posterior ethmoidal nerves, which are branches of the nasociliary nerve. The nasociliary nerve arises from the ophthalmic nerve (V1), a division of the trigeminal nerve (CN V). The trigeminal nerve is responsible for transmitting sensory information from the face, including pain, temperature, touch, and pressure. The anterior ethmoidal nerve carries pain and temperature sensations from the anterior part of the ethmoidal sinus, while the posterior ethmoidal nerve carries sensations from the posterior part. This innervation is crucial for the transmission of pain sensations from the ethmoidal sinus, which can be a source of significant discomfort and pain in various conditions such as sinusitis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the ethmoidal sinus is not innervated by the maxillary nerve (V2), which is another division of the trigeminal nerve responsible for transmitting sensations from the maxillary region.

**Option B:** This option is incorrect because the facial nerve (CN VII) is responsible for transmitting taste and motor functions of the facial muscles, not pain sensations from the ethmoidal sinus.

**Option C:** This option is incorrect because the glossopharyngeal nerve (CN IX) is responsible for transmitting sensations from the tongue, pharynx, and parts of the ear, not the ethmoidal sinus.

**Clinical Pearl / High-Yield Fact**
The trigeminal nerve is a critical nerve for the transmission of pain sensations from the face, and its three divisions (ophthalmic, maxillary, and mandibular) each have distinct areas of innervation. Understanding the innervation of the trigeminal nerve is essential for diagnosing and managing facial pain conditions.

**Correct Answer:** C.