**Core Concept**
The submandibular gland is situated close to several vital nerves, which may be at risk during surgical excision. The lingual nerve, hypoglossal nerve, and mandibular division of the trigeminal nerve are all anatomically related to the gland and require careful identification and preservation during surgery.

**Why the Correct Answer is Right**
The glossopharyngeal nerve, on the other hand, is less likely to be affected during submandibular gland excision. This is because the glossopharyngeal nerve primarily innervates the pharynx, stylopharyngeus muscle, and provides sensory input from the pharynx. Its course is more posterior and lateral to the submandibular gland, reducing the risk of injury during surgical excision.

**Why Each Wrong Option is Incorrect**
**Option A:** The lingual nerve, a branch of the mandibular division of the trigeminal nerve, is closely related to the submandibular gland and is at risk of injury during excision. It provides sensory innervation to the anterior two-thirds of the tongue.
**Option B:** The hypoglossal nerve, which innervates the muscles of the tongue, is also at risk of injury during submandibular gland excision. It is closely related to the submandibular gland and requires careful identification and preservation.
**Option D:** The mandibular division of the trigeminal nerve is responsible for the motor innervation of the muscles of mastication and the sensory innervation of the anterior two-thirds of the tongue. Its branches, including the lingual nerve, are closely related to the submandibular gland and are at risk of injury during excision.

**Clinical Pearl / High-Yield Fact**
During submandibular gland excision, it is essential to identify and preserve the lingual nerve, hypoglossal nerve, and mandibular division of the trigeminal nerve to avoid permanent nerve damage and associated complications.

✓ Correct Answer: C. Glossopharyngeal nerve