The answer is a virus. It has been a controversial topic. It is debatable which animal kingdom it belongs to. Virus' fall into the gray area because they require others to survive: to reproduce.
The Mongols and the Muslims had very different beliefs and stand points when it came to religion and organization of the society. The Mongols were pagan and during the existence of their empire big portion of them started to accept Buddhism. Unlike what their reputation was, the Mongols were actually very liberal for their time, as they didn't were not forcing people to convert to their religion, were supportive of other religion, and they were actually encouraging good relations and tolerance between the different groups. The Muslims were the opposite. They believed that everyone should live under Sharia law, everyone should be converted to Islam, and they were not tolerant at all toward other religions. This of course led to tensions and conflict between the two sides.
Answer:
The United States has few reserves and a very high consumption rate.
Explanation:
If the United States keeps using fossil fuels, they will run out very quickly and an alternative will be needed, the second answer choice supports that.