**Core Concept**
The patient's presentation suggests a case of chronic headache with a persistent fear of having a brain tumor, despite repeated examinations and normal findings. This condition is characterized by a complex interplay of psychological and neurological factors.

**Why the Correct Answer is Right**
The patient's symptoms are most likely indicative of **Chronic Daily Headache (CDH)**, which is often accompanied by anxiety, depression, and a heightened sense of somatic awareness. The patient's fear of having a brain tumor, despite normal examinations, is a classic example of **hypochondriasis**, a type of somatic symptom disorder. This condition is often seen in patients with a history of trauma, stress, or anxiety disorders.

**Why Each Wrong Option is Incorrect**
* **Option A:** **Migraine** is a possibility but is typically characterized by episodic headaches, often accompanied by aura symptoms, nausea, and photophobia. This patient's symptoms are more indicative of a chronic condition.
* **Option B:** **Cluster Headache** is a severe, debilitating headache disorder that occurs in clusters or cycles. While it can present with similar symptoms, the patient's history of continuous headache for 8 years is more suggestive of a chronic condition like CDH.
* **Option C:** **Temporal Arteritis** is a condition that typically presents with sudden onset of headache, often accompanied by visual disturbances, jaw claudication, and fever. This patient's symptoms do not align with the typical presentation of temporal arteritis.
* **Option D:** **Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)** is a condition characterized by increased intracranial pressure without any identifiable cause. While it can present with headache, the patient's symptoms and examination findings do not suggest this diagnosis.

**Clinical Pearl / High-Yield Fact**
In patients with chronic headache, it is essential to consider the psychological component and to perform a thorough psychiatric evaluation to rule out conditions like hypochondriasis and somatic symptom disorder.

**Correct Answer: C. Temporal Arteritis**