Considering the factors at the risk of developing CAD, it would be B. A 70 year old female who is obese with a LDL of 195
Explanation:
 Coronary artery disease (CAD) happens when there is an obstruction of the coronary arteries - the blood vessels that supply the heart muscle. Coronary arteries may be blocked by fat plaques depositing inside them. This process is called atherosclerosis.
  Some factors are recognized as being at risk for the development of the atherosclerotic process and, consequently, of coronary disease. Between them are: family history of coronary disease in young age,  smoking
, sedentary lifestyle,  obesity,  diabetes,  hypertension and  high levels of blood fats, particularly cholesterol.
 In A, we have a client who had a bad habit of smoking for a long time and a mitral valve prolapse, a cardiac problem in which the valve separating the upper and lower chambers of the left side of the heart does not close properly, and small amounts of blood may return to the left cavity, hampering the heart's ability to pump blood. In most cases, the cause is abnormal growth of one of the cusps. In other cases, this change is secondary to other heart diseases (such as rheumatic fever and infarction) and may also occur after valve surgery. In most cases it is harmless, and patients usually do not know they have the problem.  So depending of the cause of this injury, this client could be a risk of developing CAD.
 In B we have 2 risk factors: obsesity and high levels of LDL, which is a low density lipoprotein, popularly known as "bad" cholesterol. This fraction of total cholesterol builds up in the walls of the blood arteries, and when their levels are high also increases the risk of developing coronary heart disease such as arterial insufficiency, myocardial infarction or stroke.  Adequate LDL cholesterol levels in healthy people should be below 130 mg/dL blood, and for people at risk, the levels should not exceed 70 mg/dL.
 In C we have a client with family history of disease and an overall cholesterol below the limit, which is 190md/dL. But as he already have a CAD family history, still a client with risk.
 In D we have a client with high HDL cholesterol, which is a high density lipoprotein, popularly known as "good" cholesterol that protects us from LDL. The higher the HDL levels, the lower the risk of cardiovascular disease.  Appropriate HDL cholesterol levels should be greater than 40 mg/dL blood. Plus, the fact of using a medicine that decrease the cholesterol in blood (atorvastatin) helps on prevent of the disease.
