Bicyclists should keep what on the handlebars at all times?

Answer: B — At least one hand

Bicyclists should keep at least one hand on the handlebars at all times for several safety reasons. Maintaining control of the bicycle is crucial for navigating through traffic, making quick stops, and responding to sudden obstacles. Even when signaling a turn, it's important to keep at least one hand on the handlebars to ensure stability and control. This practice helps prevent accidents and allows the rider to react swiftly in emergencies. The other options present scenarios that compromise control and safety. Keeping both hands on the handlebars enhances stability, while having no hands reduces the rider's ability to steer effectively. Placing any type of object on the handlebars could interfere with safe riding and increase the risk of losing control. Therefore, the guideline greatly emphasizes maintaining at least one hand on the handlebars for safety.