Haemophilia is a condition, where there is
(A) no production of haemoglobin in the blood
(B) no production of melanin in the skin
(C) a failure of clotting mechanism of blood
(D) a delay in clotting of blood

Answer

To solve the question regarding the condition of Haemophilia, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Condition**: Haemophilia is a genetic disorder that affects the blood's ability to clot. It is important to know what this means in terms of bodily functions.

2. **Analyze the Options**:
- **(A) No production of haemoglobin in the blood**: This option refers to a different condition, such as anemia, not haemophilia.
- **(B) No production of melanin in the skin**: This option relates to conditions like albinism, which is unrelated to haemophilia.
- **(C) A failure of clotting mechanism of blood**: This option directly relates to what haemophilia is known for, which is the inability of blood to clot properly.
- **(D) A delay in clotting of blood**: While this may seem relevant, it does not accurately describe haemophilia, as the condition is characterized by a failure of the clotting mechanism rather than just a delay.

3. **Identify the Correct Answer**: Based on the analysis, option **(C) a failure of clotting mechanism of blood** is the correct answer. Haemophilia is specifically known for this failure, leading to excessive bleeding.

4. **Conclusion**: Therefore, the answer to the question is (C).