Final answer:
The Hours of Service cycle for commercial drivers is typically designated by the operator, though it might involve an agreement with the driver depending on specific regulations and practices.
Step-by-step explanation:
In the Hours of Service requirements, which apply to commercial drivers, there are regulations that mandate drivers to follow either a 7-day cycle or a 14-day cycle. The entity that designates the cycle a driver will comply with varies by jurisdiction. Generally, this can be determined by the motor carrier (operator) that employs the driver or, in some cases, by agreement between the driver and the operator. For example, in the US, regulations set by the Federal Motor Carrier Safety Administration (FMCSA) allow companies to choose either cycle for their drivers, while in Canada, the cycle may be designated by the operator in compliance with the National Safety Code for Motor Carriers (Standard 9). Therefore, the answer is typically B. The operator, though collaboration between the operator and the driver is also common in making such decisions.