Answer: toeboard
Explanation: The Occupational Safety and Health Administration defines the Walking-Working surfaces regulation for the secure construction of stairs in industrial environments. For platforms or walls that are 4 feet or higher above the ground and do not have surrounding walls, it is mandatory to build a standard railing around them. In cases where there is a moving machinery, people can pass or there is an equipment which would be harmful when falling objects come in contact with it, the railings must have a toeboard.
A toeboard is an equipment fixed vertically to prevent items from falling for the platform.
Usually yes. But the form of government and control that the US has is different, so they manage to manage these differences in order to be able to do their duty well in a coordinated manner.
the answer is A
hope this helps stay safe and god bless you