Answer:
Thoracic aorta.
Explanation:
Aneurysm may be defined as outward swelling or bulging weak spot on the walls of the blood vessels. Aneurysm may also initiate the clot formation or the condition of the embolization.
Thoracic aorta aneurysms is mainly responsible for the dyspnea and difficulty in swallowing known as dysphagia. This condition in cerebral vessels is mainly responsible for the headache and in renal arteries can cause flank pain.
Thus, the correct answer is option (D).