Final answer:
The statement that a mushroomed chisel or punch must be discarded is false. The tool can often be repaired by grinding off the deformed metal, though safety precautions should be taken during this process.
Step-by-step explanation:
When the head of a chisel or punch becomes "mushroomed," it indicates that the metal has deformed and spread out, resembling the shape of a mushroom. This answer to the question is B) False. Rather than discarding the tool, it is possible to repair it.
The mushroomed metal can be ground off, restoring the tool to a safe condition. However, it is crucial to wear safety goggles during this process because the weakened mushroomed metal can break off and fly out, potentially causing injury. It's important to regularly inspect and maintain tools to prevent such hazards.