What level of horizontal meridian must a driver have to meet vision standards?

To meet the vision standards set by the Federal Motor Carrier Safety Administration (FMCSA), a driver is required to have a horizontal field of vision of at least 70 degrees. This standard is crucial for ensuring that drivers can adequately detect and respond to other vehicles, pedestrians, and potential hazards on the road, thus ensuring safety for all road users.

Having a horizontal meridian of 70 degrees provides enough peripheral awareness, which is essential for safe driving. It allows the driver to have an adequate scope of vision to monitor surroundings effectively while driving, particularly in situations that require quick reflexes and situational awareness, such as changing lanes or navigating congested traffic.

Each of the other options — 50, 60, or 80 degrees — does not meet the FMCSA's minimum requirement, hence they do not satisfy the vision standards necessary for a commercial driver. Thus, the correct choice underscores the importance of visual capability in driving safety.