The answer to this is A. There is a need for natural gas to be transported through pipelines. Are you familiar with what natural gas is? This is the type of gas that usually comes deeply from the surface of the earth. This may come with a lot of compounds. One of the most abundant compounds that you can find right now is methane.
This usually comes with a carbon atom and four hydrogen atoms. Take note that there are still other alkanes that are present. There are also instances when small amounts of carbon dioxide may also be available. Natural gas is used for different processes right now but some are saying that it might not last forever.