Step 1: List the parts of a household refrigerator:
A household refrigerator works on the vapour compression cycle. It has a compressor, a condenser, an expansion device (capillary tube) and an evaporator.
Step 2: Understand A.H.U.:
A.H.U. stands for Air Handling Unit. It is a large unit used in central air conditioning plants.
It has a fan, a cooling coil and filters to treat and send air through ducts.
Step 3: Check the other options:
The condenser rejects heat to the surroundings, so (A) is present.
The evaporator absorbs heat from the cabinet, so (C) is present.
The compressor circulates the refrigerant, so (D) is present.
Final Answer:
The A.H.U. is not part of a household refrigerator. This is option (B).