Final answer:
A two-dimensional echocardiographic finding of an aortic intimal flap indicates aortic dissection.
Step-by-step explanation:
The two-dimensional echocardiographic finding of an aortic intimal flap indicates aortic dissection, which is option B. Aortic dissection is a serious condition where a tear occurs in the inner layer of the aorta, causing blood to flow between the layers of the artery wall. This can lead to a life-threatening situation if not promptly diagnosed and treated.