**Core Concept**
Altered sensorium is a clinical presentation of impaired consciousness or altered mental status, which can be caused by various factors including neurological, metabolic, or toxic disorders. This condition can manifest as confusion, disorientation, or decreased level of consciousness.

**Why the Correct Answer is Right**
Altered sensorium following headache and vomiting may be indicative of increased intracranial pressure (ICP) due to a space-occupying lesion, such as a subarachnoid hemorrhage or intracerebral hemorrhage. The headache and vomiting are classic symptoms of raised ICP, which can lead to impaired consciousness. The Cushing's reflex, characterized by increased ICP, bradycardia, and hypertension, may also be present.

**Why Each Wrong Option is Incorrect**
**Option A:** Not enough information is provided to determine if this option is relevant.
**Option B:** Not applicable to the given scenario.
**Option C:** Not directly related to the symptoms described.
**Option D:** Not relevant to the clinical presentation of altered sensorium following headache and vomiting.

**Clinical Pearl / High-Yield Fact**
The Cushing's reflex is a classic sign of increased ICP and can be remembered by the mnemonic "C-3-H": Cushing's reflex, Cushing's disease, Cushing's syndrome, and hypertension.

**Correct Answer:** C. Intracranial hemorrhage.