Ascorbic acid is the chemical name of Vitamin C. It is a water-soluble vitamin that acts as an antioxidant and is essential for the synthesis of collagen in connective tissues. Its deficiency leads to scurvy, a disease characterized by bleeding gums, loose teeth, and delayed wound healing.
- (A) Vitamin: Correct, because ascorbic acid is Vitamin C.
- (B) Enzyme: Wrong, enzymes are biological catalysts, not vitamins.
- (C) Protein: Wrong, proteins are polymers of amino acids, not vitamins.
- (D) Hormone: Wrong, hormones are chemical messengers secreted by glands, not vitamins.
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\boxed{\text{Vitamin (Vitamin C)}}
\]