**Core Concept**
Kwashiorkor and marasmus are two forms of malnutrition, characterized by distinct pathophysiological processes. Both conditions result from inadequate nutrition, but the primary difference lies in the presence or absence of edema.

**Why the Correct Answer is Right**
Both kwashiorkor and marasmus are forms of protein-energy malnutrition (PEM). In kwashiorkor, there is a relative deficiency of protein, leading to impaired synthesis of essential proteins and enzymes. This results in edema due to hypoalbuminemia. In marasmus, there is a severe deficiency of both protein and energy, leading to muscle wasting and weight loss. Despite these differences, both conditions share the commonality of inadequate nutrition.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incomplete.
**Option B:** This option is not a characteristic shared by both conditions.
**Option C:** This option is incorrect as both conditions have distinct pathophysiological processes.

**Clinical Pearl / High-Yield Fact**
Both kwashiorkor and marasmus can be prevented by ensuring adequate nutrition, particularly protein and energy intake. Early detection and treatment of malnutrition are crucial in preventing long-term complications.

**Correct Answer:** B. Both diseases have inadequate nutrition.