Pernicious anaemia is due to the deficiency of

Options

A. iron
B. cobalamin
C. calciferol
D. phylloquinone

Answer

To solve the question regarding pernicious anemia, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks about the deficiency that leads to pernicious anemia.

2. **Identify the Options**: The options provided are:
- Iron
- Cobalamin
- Calciferol
- Phylogenol

3. **Recall Information about Pernicious Anemia**: Pernicious anemia is also known as megaloblastic anemia. It is characterized by the production of large, abnormal red blood cells.

4. **Determine the Cause**: Pernicious anemia is primarily caused by a deficiency of vitamin B12, which is also referred to as cobalamin.

5. **Select the Correct Answer**: Since cobalamin is the same as vitamin B12, the correct answer to the question is **Cobalamin**.

6. **Conclusion**: Therefore, pernicious anemia is due to the deficiency of cobalamin (vitamin B12).

### Final Answer:
Pernicious anemia is due to the deficiency of **Cobalamin (Vitamin B12)**.

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