Why is it important for a truck to have properly functioning turn signals?

Having properly functioning turn signals is crucial for safety on the road because they serve as a means of communication between drivers. When a truck driver uses turn signals, they indicate their intentions to change lanes or make turns to other road users, including other vehicles, cyclists, and pedestrians. This helps to prevent accidents and promotes smoother traffic flow, as other drivers can anticipate movements and adjust their actions accordingly.

The other options do not directly relate to the main purpose of turn signals. While saving energy, increasing speed, and reducing fuel consumption are important factors related to vehicle operation, they do not address the primary function of turn signals as a safety feature. The emphasis on communication underscores the importance of road safety and the role of signals in preventing misunderstandings between drivers.