Question

what is a solution to reduce greenhouse gas emissions from transportation? use public transportation or carpool. use more plastic bags. leave engines running when not moving. drive alone in a gasoline car every day.

Explanation:

Using public transportation or carpooling reduces the number of vehicles on the road, thus decreasing greenhouse gas emissions from transportation. Using more plastic bags is not related to transportation emissions. Leaving engines running when not moving (idling) wastes fuel and increases emissions. Driving alone in a gasoline car every day increases the number of vehicles emitting greenhouse gases.

Answer:

Use public transportation or carpool.