Final answer:
The maximum allowed distance between a spark breaker and tool rest from a wheel is 1/4 inch, which is a safety standard not provided in the given options, to prevent hazardous situations.
Step-by-step explanation:
The maximum distance that a spark breaker and tool rest should be from a wheel is 1/4 inch. This is a safety guideline to prevent workpieces from becoming lodged between the wheel and the rest, which could result in wheel damage or a hazardous situation. The correct answer to the question is not listed among the options (a) 1 inch, (b) 2 inches, (c) 3 inches, (d) 4 inches. It is important to adhere strictly to safety standards when operating machinery to avoid accidents and maintain a safe working environment.