**Core Concept**
The DASH (Dietary Approaches to Stop Hypertension) diet is a dietary plan that aims to reduce blood pressure by emphasizing nutrient-dense foods and limiting sodium intake. This dietary approach is based on the principle of reducing sodium consumption and increasing potassium intake to help lower blood pressure.

**Why the Correct Answer is Right**
The DASH diet focuses on whole grains, fruits, vegetables, lean protein, and low-fat dairy products. By emphasizing these food groups, individuals can increase their potassium intake, which helps to counteract the effects of sodium and reduce blood pressure. The DASH diet also recommends limiting foods high in sodium, added sugars, and saturated fats. This approach is supported by the National Heart, Lung, and Blood Institute (NHLBI) and has been shown to be effective in reducing blood pressure in individuals with hypertension.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the DASH diet is not primarily focused on reducing carbohydrate intake.
**Option B:** This option is incorrect because the DASH diet does not emphasize a low-carbohydrate or ketogenic approach.
**Option C:** This option is incorrect because the DASH diet is not specifically designed for weight loss, although weight loss may be a secondary benefit.

**Clinical Pearl / High-Yield Fact**
The DASH diet is a well-studied and effective approach to reducing blood pressure and promoting overall cardiovascular health. It is a good example of how lifestyle modifications, including dietary changes, can have a significant impact on chronic disease management.

**Correct Answer: B. The DASH diet is a dietary plan that emphasizes whole grains, fruits, vegetables, lean protein, and low-fat dairy products to reduce blood pressure.**