Step 1: Understanding the Concept:
Vitamins are essential organic micronutrients that human bodies require in small quantities to regulate vital metabolic and biochemical functions. Based on their molecular structures and solubility behaviors, vitamins are classified into two main categories:
1. Water-Soluble Vitamins: Dissolve easily in water. They are quickly excreted by the body through urine and need to be replenished constantly in our diet.
2. Fat-Soluble Vitamins: Dissolve in organic lipid environments and fats. They are absorbed through the intestinal tract with the help of dietary fats and can be stored long-term in the liver and adipose fatty tissues.
Step 2: Detailed Explanation:
Let's sort the listed vitamins based on their solubility groups:
- Vitamin A: Fat-soluble (crucial for healthy vision and immune health).
- Vitamin B: Water-soluble (this includes the entire complex group such as $\text{B}_1, \text{B}_2, \text{B}_6, \text{B}_{12}$, etc.).
- Vitamin C: Water-soluble (ascorbic acid, found in citrus fruits—though not listed in the main options, it belongs to this class).
- Vitamin D: Fat-soluble (synthesized in skin exposed to sunlight; essential for calcium absorption).
- Vitamin E: Fat-soluble (acts as a powerful lipid-protecting antioxidant).
- Vitamin K: Fat-soluble (necessary for synthesis of blood-clotting proteins).
Reviewing our categorized items, statements (A), (C), (D), and (E) represent the fat-soluble group, while statement (B) must be excluded. This selection corresponds to option (C).
Step 3: Final Answer:
The fat-soluble vitamins are (A), (C), (D) and (E) only, matching option (C).