Concept
Milk is an emulsion/colloidal liquid whose major constituent is water (~85–90%).
 
Option check
 
 - Cream — fat fraction that can be removed; not always present in processed/skim milk.
  - Curd — a fermented/precipitated form, not inherent to all milk.
  - Water — universal constituent; necessary.
  - Whiteness — typical appearance but can vary (off-white/yellowish); appearance is not a chemical constituent.
  
  
Final Answer
 Water is necessarily present in milk. 
 
			
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