**Core Concept**
Kwashiorkor is a severe form of malnutrition characterized by edema, muscle wasting, and impaired growth and development. It is typically caused by a lack of protein in the diet, often in conjunction with adequate caloric intake.

**Why the Correct Answer is Right**
The characteristic features of kwashiorkor include edema, muscle wasting, and impaired growth and development. The edema in kwashiorkor is due to the lack of albumin, a protein that helps maintain fluid balance in the body. The liver is also affected in kwashiorkor, leading to an accumulation of fat and an increase in the activity of certain liver enzymes. The characteristic "pot belly" seen in kwashiorkor is due to the accumulation of fat in the abdominal cavity.

**Why Each Wrong Option is Incorrect**
**Option A:** Edema is indeed a characteristic feature of kwashiorkor, so this option is incorrect.
**Option B:** Muscle wasting is also a characteristic feature of kwashiorkor, making this option incorrect.
**Option C:** Impaired growth and development are common in children with kwashiorkor, so this option is incorrect.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that kwashiorkor can be distinguished from marasmus, another form of malnutrition, by the presence of edema in kwashiorkor.

**Correct Answer: D.**