Which of these energy resources is estimated to be the most abundant? A. Petroleum B. Gas Hydrates C. Natural Gas

It is not coal. I know that for sure, that is why it's not an option here.

Hydrates

Explanation:

they're the most abundant source of natrual gas. "Hydrates are a much more abundant source of natural gas than conventional deposits. According to the U. S. Geological Survey, global stocks of gas hydrates range account for at least 10 times the supply of conventional natural gas deposits, with between 100,000 and 300,000,000 trillion cubic feet of gas yet to be discovered."