Final answer:
Pipe labels are commonly required at intervals of every 50 feet according to ANSI/ASME A13.1, which doesn't match the options provided in the question. It's advised to consult the specific regulations for the correct interval, but if limited to the choices provided, the closest is D) 25 feet.
Step-by-step explanation:
The question pertains to the standards for labeling pipes in a facility to ensure safety and compliance with regulations. According to common industry standards, such as those outlined by ANSI/ASME A13.1, pipe labels shall be located at intervals of no more than every 50 feet for straight runs of pipe, at every point of change in direction, adjacent to all valves and flanges, on both sides of walls and floors penetrated by pipes, and at any other point where identification is necessary due to changes in elevation or other potential obstructions to view. None of the options provided (A) 10, (B) 15, (C) 20, (D) 25 match the standard 50-foot interval. Therefore, it is possible that the question may contain a typo or misunderstanding. It would be advisable to consult the specific regulations or standards that apply to the context of the pipe being labeled to determine the correct answer. Without additional context, if the choices provided are strict, the closest to common standards would be D) 25, but users should verify the standards specific to their application.