Which one of the following diseases is caused mainly by the deficiency of Vitamin C?

Scurvy

The correct answer is Option (3) - Scurvy

The disease mainly caused by the deficiency of Vitamin C is: Scurvy

Scurvy is a condition caused by a deficiency of Vitamin C (ascorbic acid) in the diet. Vitamin C is essential for the synthesis of collagen, a protein that is important for the structure and maintenance of connective tissues, skin, blood vessels, and bones. Without an adequate supply of Vitamin C, collagen synthesis is impaired, leading to various symptoms such as weakness, fatigue, swollen and bleeding gums, joint pain, bruising, and skin problems.