Deficiency in the activity of adrenal cortex leads to

Options

A. Cushing's disease
B. Conn's syndrome
C. Addison's disease
D. Simmond's disease

Answer

### Step-by-Step Solution:

1. **Understanding the Adrenal Cortex**: The adrenal cortex is the outer layer of the adrenal glands and is responsible for producing several hormones, including cortisol and aldosterone.

2. **Identifying Hormones**: Cortisol is a steroid hormone that helps regulate metabolism, immune response, and stress. Aldosterone is involved in regulating blood pressure and electrolyte balance.

3. **Recognizing Deficiency Effects**: A deficiency in the activity of the adrenal cortex means that there is not enough production of these hormones. This can lead to various health issues.

4. **Identifying the Disease**: The condition caused by the deficiency of adrenal cortex hormones is known as Addison's disease. This disease can affect individuals of all ages and both sexes and can sometimes be life-threatening.

5. **Choosing the Correct Option**: From the options provided:
- A) Cushing's disease - caused by excess cortisol
- B) Kohn's disease - not a recognized condition related to adrenal deficiency
- C) Addison's disease - caused by adrenal cortex deficiency
- D) Simon's disease - not a recognized condition related to adrenal deficiency

The correct answer is **C) Addison's disease**.

### Final Answer:
Deficiency in the activity of the adrenal cortex leads to **Addison's disease**.

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