Final answer:
All listed options are true safety guidelines for grinding practices, making 'All of the Above' the incorrect statement as it suggests otherwise. Therefore, the correct option is A.
Step-by-step explanation:
The statement "All of the following are TRUE except for: -Do not use a wheel that has been dropped, -Do not grind wood, plastics and non-iron metals, -Do not grind on the face of a regular wheel, -All of the Above" presents safety guidelines related to grinding practices. The correct answer should be the option that is not a recommended safety guideline.
It's important to never use a grinding wheel that has been dropped, as it may be cracked or otherwise damaged, potentially causing an accident when spun at high speeds. Additionally, grinding materials like wood, plastics, and non-iron metals may not be suitable for a regular grinding wheel as these materials could clog or damage the wheel, and there could be safety concerns with the wheel materials themselves. However, 'Do not grind on the face of a regular wheel' is a true guideline as well; you should use the wheel’s edge for grinding, unless it is specifically designed for face grinding.
Therefore, 'All of the Above' is the incorrect option since all listed statements are actually true safety guidelines.