Why should the driver not signal another vehicle to overtake and pass?

Answer: B — Because it may encourage them to overdrive their ability

While it is important to conserve fuel while driving, signaling another vehicle to overtake and pass is not a significant factor in fuel consumption. Additionally, it is not illegal to signal another vehicle to overtake and pass in most situations. The major concern is that signaling to overtake and pass may encourage the other driver to drive beyond their abilities, potentially leading to a dangerous situation for both drivers. Hence, it is best to avoid signaling for another driver to overtake and pass unless absolutely necessary.