Final answer:
When driving in the left lane with a faster vehicle approaching from behind, you should safely move to the right lane to allow the vehicle to pass. This follows both road safety and etiquette.
Step-by-step explanation:
If you are driving in the left lane and a vehicle behind you is operating at a higher speed, the appropriate action to take is to move to the right lane when it is safe to do so, allowing the faster vehicle to pass. It's important for safety and to follow traffic laws to not obstruct the flow of traffic by remaining in the left lane, which is often designated for passing or faster-moving traffic. You should not speed up to match the vehicle's speed as it could lead to speeding violations and unsafe conditions, or slow down abruptly which can also cause unsafe conditions or traffic incidents. Additionally, common courtesy and road etiquette typically dictate that slower-moving traffic keeps to the right.