To order the activities from greatest to least impact in reducing fossil fuel consumption, we should consider the amount of fossil fuels consumed by each option.
- Walk to work - This has the greatest impact since it completely eliminates the use of fossil fuels for transportation.
- Carpool to work - This reduces the number of vehicles on the road, leading to lower fossil fuel consumption compared to driving alone.
- Drive an electric car to work - While this reduces fossil fuel use, it may still require fossil fuels if the electricity is generated from non-renewable sources.
- Drive alone to work - This has the least impact as it involves the highest fossil fuel consumption since you're using a car solely for your commute.
So the correct order from greatest to least impact is: walk to work, carpool to work, drive an electric car to work, drive alone to work.
However, since "walk to work" and "carpool to work" are the options given, this specific ordering may not be apparent in the provided responses. But based on the activities, the answer would be closest to "walk to work, carpool to work, drive alone to work."
Therefore, the best match from your responses is: walk to work, carpool to work, drive alone to work.