Which operation is described as making square objects?

• A. Milling
• B. Casting
• C. Welding
• D. Finishing

Answer: (A)

Milling is the process that creates square objects by removing material with a rotating cutting tool. In milling, a workpiece is held in a milling machine and cut with end mills or face mills to produce flat surfaces and sharp, right-angle edges. This subtractive method lets you shape stock into square blocks or parts with precise dimensions. Casting forms shapes by pouring material into a mold and may produce squares, but milling directly achieves the clean, squared geometry through controlled material removal. Welding joins pieces, and finishing mainly improves surface quality without defining geometric form. So milling best describes making square objects.