turning down the volume on the television using biodegradable materials using public transportation instead of driving recycling paper
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which of these daily activities can most directly help reduce air pollution in a city?
Possibilities:
- turning down the volume on the television
- using biodegradable materials
- using public transportation instead of driving
- recycling paper

using public transportation instead of driving