Step 1: Understanding the Concept:
Milk sampling requires proper mixing.
Specific equipment is used for mixing.
Step 2: Key Formula or Approach:
No specific formula.
Need to know the equipment for mixing milk.
Step 3: Detailed Explanation:
A plunger is used for proper mixing of milk in a can.
It ensures uniform distribution of fat.
Sampling dipper and tube are used for collecting samples.
Compressed air is not used for mixing.
Thus, a plunger is the correct equipment.
Step 4: Final Answer:
A plunger is useful for mixing milk.
Hence, the correct option is (A).
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