What must a learner driver always have when operating a vehicle?

Answer: B — qualified supervisor in the front seat

A learner driver is required to have a qualified supervisor in the front seat when operating a vehicle. This stipulation ensures that the learner has immediate access to guidance and support from an experienced driver, which is crucial for enhancing safety and learning. The qualified supervisor must hold a full driver's license and have a good understanding of driving rules and responsibilities. This measure is designed to create a safer environment for not only the learner but also for other road users. The supervisor can provide real-time feedback, help in managing risks, and reinforce good driving practices, contributing to the learner's development and readiness to take on the responsibilities associated with driving independently.