Which artery supplies blood to the head and brain?

The carotid artery is the principal vessel responsible for supplying blood to the head and brain. There are two main carotid arteries—the left and right—that branch off from the aorta and ascend to the head. As each carotid artery reaches the level of the jaw, it bifurcates into the internal and external carotid arteries. The internal carotid artery is crucial for delivering oxygen-rich blood directly to the brain, while the external carotid artery supplies blood to the face and neck.

In the context of the other options, the radial artery primarily serves the forearm and hand, while the femoral artery supplies blood to the thigh and lower limb. The aorta, although it is the largest artery in the body and facilitates the flow of oxygenated blood from the heart to the rest of the body, does not supply blood exclusively to the head and brain. Thus, the carotid artery stands out as the vessel that plays a critical role in ensuring adequate blood flow to these vital areas.