Final answer:
It is typically not safe or permissible for an employee to ride the leading and platform of a tank car unless the railroad has authorized it and appropriate safety measures are implemented.
Step-by-step explanation:
The question is asking whether it is acceptable for an employee to ride the leading and platform of a tank car under certain conditions. The correct answer is C. No, unless authorized by the railroad. This is a safety regulation that must be followed to prevent accidents and injuries.
It is generally unsafe and against regulations for employees to ride on parts of a train that are not designed for travel, especially when the train is in motion. An exception to this rule would only be if the railroad has specifically authorized it, which would include appropriate safety measures being in place.