**Core Concept**
The question targets the concept of drug therapy for angina pectoris, specifically focusing on the role of vasodilation in managing this condition. Angina pectoris is a symptom of myocardial ischemia, often caused by atherosclerotic coronary artery disease. Vasodilatory drugs are commonly used to alleviate angina symptoms by increasing blood flow to the ischemic myocardium.

**Why the Correct Answer is Right**
The correct answer is a drug that does not rely on vasodilation to exert its effects. Nitroglycerin, for example, is a vasodilator that causes venous dilation, reducing preload and subsequently myocardial oxygen demand. However, the question seeks a drug that achieves its effects through a different mechanism. Beta-blockers, such as **metoprolol** (Option C), are effective in angina by reducing heart rate, contractility, and myocardial oxygen demand, thereby alleviating ischemia. This is achieved through beta-1 receptor blockade in the heart, without causing significant vasodilation.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided.
* **Option B:** This option is not provided.
* **Option C:** Not applicable, as this is the correct answer.
* **Option D:** This option is not provided.

**Clinical Pearl / High-Yield Fact**
Beta-blockers are a cornerstone in the management of angina, particularly in patients with stable angina or those undergoing coronary artery bypass grafting. They reduce the risk of myocardial infarction and mortality in these patients.

**Correct Answer:** C. Metoprolol