Question The driver of a commercial motor vehicle: Answers Can use any cell phone while driving. Can only use a hands-free mobile phone while driving. Can only use a cell phone on rural roads. Can use a cell phone at night. Explanation It is prohibited for CMV drivers to use hand-held mobile phones while driving. This questions appears in the following tests: Connecticut Class B Knowledge Test Nebraska Class A Knowledge Test Nebraska Class A Knowledge Test New Hampshire Class A Knowledge Test South Carolina Class B Knowledge Test South Dakota Double