The answer is oil.
The United States' fossil shortage of oil makes the country dependent on outside sources. Mineral oil such as crude oil or commonly known as petroleum came from the ancient fossilized organic materials. This resource is limited. The US is now facing a shortage in oil and becoming dependent to some countries such as middle-east countries.
It is also assists in creating body chemicals like hormones and enzymes that are needed for normal function. It provides energy (like carbohydratesdo) and keeps the immune system strong. Proteins are made up of amino acids, and dogs require 22 amino acids to make necessary proteins.
