Diabetes mellitus is due to 

Options

A. Insulin
B. Glucagon
C. Thyroxine
D. Adrenaline

Answer

**Step-by-Step Solution:**

1. **Understanding Diabetes Mellitus**: Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels. This condition arises when the body cannot effectively use insulin or does not produce enough insulin.

2. **Role of Insulin**: Insulin is a hormone produced by the pancreas. Its primary function is to facilitate the uptake of glucose from the bloodstream into the cells, where it can be used for energy or stored as glycogen in the liver and muscles.

3. **Deficiency of Insulin**: In diabetes mellitus, there is a deficiency of insulin. This deficiency can occur due to various reasons, including autoimmune destruction of pancreatic beta cells (Type 1 diabetes) or insulin resistance (Type 2 diabetes).

4. **Consequences of Insulin Deficiency**: When there is insufficient insulin, glucose remains in the bloodstream instead of being converted into glycogen. This leads to elevated blood glucose levels, which can cause various health complications if not managed properly.

5. **Conclusion**: Therefore, diabetes mellitus is primarily due to the deficiency of the hormone insulin.

**Final Answer**: Diabetes mellitus is due to the deficiency of insulin.

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