Question

Technician A says that to prevent the machine from starting by accident when you're working on it, disconnect the ignition system before starting work. Technician B says that one of the most important parts of any safety-and-accident-prevention program is good housekeeping. Who is correct?

Answer 1

Both Technician A and Technician B are correct. 
When working on an ignition system, it is important to make sure it is turned off, because any spark or incidental flow of energy could result in a serious accident. 
Technician B is correct that good house-keeping is essential to accident prevention. Keeping the work area neat, clean, and free of debris and other substances goes a long way in preventing an accident. A messy, dirty work area prevents many obstacles and hazards and can result in injury or worse. 

Answer 2

Both technicians A and B are correct.