Step 1: Understanding the Concept:
Milk constituents are classified based on their specificity.
Some are organ-specific, others are species-specific.
Step 2: Key Formula or Approach:
No specific formula.
Need to know the specificity of milk constituents.
Step 3: Detailed Explanation:
Lactose is organ-specific (found in mammary gland).
It is not species-specific (found in milk of most mammals).
Fat, vitamins, and salts are not organ-specific.
Thus, lactose is organ-specific but not species-specific.
Step 4: Final Answer:
Lactose is organ-specific but not species-specific.
Hence, the correct option is (C).
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