Final answer:
Coronary angiography is the best test to assess for coronary re-occlusion after an MI as it allows direct visualization of the coronary arteries to check for blockages.
Step-by-step explanation:
The best test to assess for coronary re-occlusion after a myocardial infarction (MI) is c) Coronary angiography. This procedure involves the use of contrast material to visualize the coronary arteries, which can reveal if there is a re-occlusion. Echocardiography can provide information on the heart's structure and function but is less suitable for directly assessing the coronary arteries. Stress tests, such as those involving thallium-201, assess cardiac function during exercise and can indicate areas of reduced blood flow, but they do not provide a direct look at the coronary arteries. Cardiac MRI offers a detailed view of the cardiac structures and can assess the aftermath of an MI, but it is not the primary choice for evaluating the patency of coronary arteries.