Final answer:
To drive very slowly off the highway, the Low gear should be used, as it offers better control and engine braking at low speeds.
Step-by-step explanation:
When needing to drive very slowly off the highway, the appropriate gear to use is Low (often labeled as 'L' on an automatic transmission selector). This setting provides increased engine power at low speeds, which is suitable for situations where fine control of speed is necessary, such as off-road driving or navigating through obstacles. Using Low gear also provides engine braking, which can be helpful on steep declines. It is important not to confuse Low gear with other settings such as Reverse, Park, or Neutral, which serve different purposes and are not designed for regular driving conditions.