**Core Concept**
The management of hypertension in the elderly requires careful consideration of the potential risks and benefits of different antihypertensive agents. The ideal choice should minimize the risk of adverse effects, such as orthostatic hypotension, while effectively lowering blood pressure.

**Why the Correct Answer is Right**
The correct answer is **D (diuretics)**. Diuretics are often the preferred initial treatment for hypertension in the elderly due to their efficacy in reducing blood pressure, particularly in patients with fluid retention or heart failure. They work by increasing urine production, which helps to lower blood volume and pressure. The most commonly used diuretics in this context are thiazide diuretics, such as hydrochlorothiazide.

**Why Each Wrong Option is Incorrect**
**Option A:** ACE inhibitors are not the first choice for elderly patients with hypertension due to their potential side effect of cough and the risk of hyperkalemia, especially in patients with renal impairment.
**Option B:** Beta blockers can be used to treat hypertension in the elderly, but they may not be the best initial choice due to their potential to worsen heart failure and their effects on glucose and lipid metabolism.
**Option C:** Calcium channel blockers can be effective in treating hypertension, but they may not be the best initial choice for elderly patients due to their potential side effects, such as edema and dizziness.

**Clinical Pearl / High-Yield Fact**
The American College of Cardiology and the American Heart Association recommend diuretics as a first-line treatment for hypertension in patients over 60 years old due to their effectiveness and safety profile.

**Correct Answer: D. Diuretics.**