Which of the following vitamin is known as Nicotinic acid ?

Options

A. `B_(1)`
B. `B_(2)`
C. `B_(3)`
D. `B_(5)`

Answer

To solve the question "Which of the following vitamin is known as Nicotinic acid?", follow these steps:

### Step-by-Step Solution:

1. **Identify the Vitamin in Question**: The question asks for the vitamin that is known as Nicotinic acid.

2. **Recall Vitamin Names**: Familiarize yourself with the names of various vitamins and their corresponding numbers. Vitamins are often referred to by both their common names and their numerical designations (e.g., Vitamin B1, B2, B3, etc.).

3. **Know the Specifics of Vitamin B3**: Vitamin B3 is also known as Niacin. It is important to note that Niacin is synonymous with Nicotinic acid.

4. **Confirm the Structure**: Vitamin B3 (Niacin/Nicotinic acid) has a specific chemical structure, which includes a pyridine ring with a carboxylic acid group. This structure is represented as C6H5NO2, which is indicative of its classification.

5. **Water Solubility**: Recognize that Vitamin B3 is a water-soluble vitamin, which is a characteristic of several B vitamins.

6. **Select the Correct Option**: Based on the above information, you can conclude that the vitamin known as Nicotinic acid is indeed Vitamin B3.

### Final Answer:
Vitamin B3 is known as Nicotinic acid.

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