**Core Concept**
The posterior cerebral artery (PCA) supplies blood to the posterior aspect of the brain, including the occipital lobe, thalamus, and parts of the temporal and parietal lobes. It is a critical branch of the vertebrobasilar system, which also includes the vertebral arteries and the basilar artery.

**Why the Correct Answer is Right**
The PCA typically arises from the basilar artery, which is formed by the fusion of the two vertebral arteries. This occurs at the level of the pontomedullary junction. The PCA then courses laterally and superiorly, supplying blood to the aforementioned brain regions. The PCA is responsible for the blood supply to the visual cortex, making it a vital structure for vision and visual processing.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the PCA does not typically arise from the internal carotid artery. While it is possible for some variations to occur, the PCA's origin from the basilar artery is the most common and clinically relevant scenario.

**Option B:** This option is incorrect because the PCA does not arise from the anterior cerebral artery. The anterior cerebral artery supplies blood to the medial aspect of the brain, including the medial frontal and parietal lobes, and is not directly related to the PCA's origin.

**Option C:** This option is incorrect because the PCA does not arise from the middle cerebral artery. The middle cerebral artery supplies blood to the lateral aspect of the brain, including the frontal, parietal, and temporal lobes, and is not directly related to the PCA's origin.

**Clinical Pearl / High-Yield Fact**
Remember that the PCA's origin from the basilar artery can be affected by various pathologies, including atherosclerosis, aneurysms, and arteriovenous malformations, which can lead to visual disturbances and other neurological deficits.

**Correct Answer:** C. Basilar artery