**Core Concept**
Amaurosis fugax is a transient monocular visual loss, often described as a curtain or shade descending over one eye. It is typically caused by a temporary reduction in blood flow to the eye, usually due to atherosclerotic plaque formation in the carotid arteries or other large vessels.

**Why the Correct Answer is Right**
Amaurosis fugax is often associated with carotid artery disease, and visual loss can be a warning sign of an impending stroke. The mechanism involves embolization of atherosclerotic material, leading to a temporary blockage of the ophthalmic artery or its branches. This condition can also be caused by vasculitis, vasospasm, or other vascular disorders.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not typically associated with amaurosis fugax.
**Option B:** This is a common cause of amaurosis fugax, so it must be the correct answer.
**Option C:** This option is not directly related to the pathophysiology of amaurosis fugax.
**Option D:** This option is a symptom of amaurosis fugax, rather than a cause.

**Clinical Pearl / High-Yield Fact**
Amaurosis fugax is a "warning stroke" that can precede a full-blown ischemic stroke, emphasizing the importance of prompt evaluation and treatment of carotid artery disease.

**Correct Answer: B. Amaurosis fugax is often associated with carotid artery disease, and visual loss can be a warning sign of an impending stroke.**