Before power to a lathe is turned on, it is a good shop practice to first hand feed the carriage to ensure __________.

Correct Answer: Option C — all locking devices have been released

Manual movement of the carriage before engaging power is a critical safety practice to verify that all locking devices, such as the carriage lock, are disengaged. This prevents mechanical damage to the lathe's lead screw or feed rod and ensures the carriage can travel freely without obstruction during operation.