## **Core Concept**
The question involves a clinical scenario with a 70-year-old male presenting with hypo-aesthesia of the external auditory meatus and a positive Hitzelberg's sign. This points towards a condition affecting the facial nerve, specifically the nerve's sensory branch that supplies the external auditory meatus.

## **Why the Correct Answer is Right**
The correct answer, **Facial Nerve (VII)**, is implicated because the facial nerve has a sensory branch that supplies the external auditory meatus. Hitzelberg's sign, which involves diminished sensation in the external auditory canal, is indicative of facial nerve involvement. The facial nerve is responsible for controlling the muscles of facial expression and transmits taste from the anterior two-thirds of the tongue. It also has a sensory component that supplies the external auditory meatus.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is blank and cannot be evaluated.
- **Option B:** This option is blank and cannot be evaluated.
- **Option C:** This option is blank and cannot be evaluated.
- **Option D:** This option is blank and cannot be evaluated.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that the facial nerve has a small sensory branch known as the nervus intermedius (of Wrisberg), which carries sensory fibers from the face (including the external auditory meatus) and taste fibers from the anterior two-thirds of the tongue. The presence of Hitzelberg's sign can be an early indicator of facial nerve pathology, such as in conditions leading to facial paralysis.

## **Correct Answer Line**
**Correct Answer: B. Facial Nerve (VII).**