A 72-Year-Old Woman Is Brought to the Emergency Department Due

A 72-year-old woman is brought to the emergency department due to right lower extremity weakness. The patient developed difficulty with walking this morning. She does not complain of headaches, nausea, disturbed vision, or back pain. The patient has a medical history of hypertension, diabetes mellitus, and coronary disease. Temperature is 37 C (98.6 F) , blood pressure is 150/95 mm Hg, pulse is 120/min, and irregularly irregular. On examination, right lower extremity power is 0/5, deep tendon reflex is +2. The Babinski sign is present. Otherwise, the left side examination is normal. A thrombus involving which of the following structures explains the patient's symptoms?

A) Anterior spinal artery of the lumbosacral region
B) Left posterior inferior cerebellar artery
C) Lumbosacral spinal neuroforamina
D) Right anterior cerebral artery
E) Right middle cerebral artery