Failure or reduced insulin production causes

Options

A. Diabetes mellitus
B. Diabetes insipidus
C. Addison's disease
D. Cushing's disease

Answer

### Step-by-Step Solution:

1. **Understanding Insulin's Role**: Insulin is a hormone produced by the pancreas that regulates blood sugar levels. It facilitates the uptake of glucose by cells, thereby lowering blood sugar levels.

2. **Identifying the Consequence of Reduced Insulin**: When there is a failure or reduced production of insulin, the body cannot effectively lower blood sugar levels. This leads to an increase in blood sugar levels, a condition known as hyperglycemia.

3. **Linking Hyperglycemia to Diabetes Mellitus**: The condition characterized by high blood sugar levels due to insufficient insulin is known as diabetes mellitus. This is the primary disorder associated with insulin deficiency.

4. **Excluding Other Options**:
- **Diabetes Insipidus**: This condition is unrelated to insulin. It involves a deficiency of the antidiuretic hormone (ADH), leading to excessive urination and thirst.
- **Addison's Disease**: This is caused by the hyposecretion of steroid hormones (like cortisol and aldosterone) from the adrenal glands, not insulin.
- **Cushing's Disease**: This condition results from the overproduction of cortisol, not a deficiency of insulin.

5. **Conclusion**: Based on the understanding of insulin's role and the consequences of its deficiency, the correct answer to the question is diabetes mellitus.

### Final Answer:
Failure or reduced insulin production causes **diabetes mellitus**.

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