The correct answer is option 2, Ascorbic acid. Ascorbic acid is commonly known as Vitamin C. It is an essential nutrient for the human body and plays a vital role in maintaining overall health. It is classified as a water-soluble vitamin, meaning it dissolves in water and is not stored in the body.

Option 1, Methanoic acid, is also known as formic acid. Although it is an organic acid, it is not associated with vitamin C.

Option 3, Lactic acid, is a different type of organic acid. It is produced in the body as a byproduct of muscle metabolism during exercise and can cause muscle soreness.

Option 4, Tartaric acid, is a naturally occurring organic acid found in many fruits, such as grapes. It is commonly used as an acidulant in the food and beverage industry, but it is not associated with vitamin C.

In conclusion, the correct answer is option 2, Ascorbic acid, which is known as Vitamin C.