The correct answer to number 1 is to outcompete rival businesses.
By lowering prices, Standard Oil Company ensured that citizens and other companies bought their product. This resulted in decreased competition, as other businesses could not compete with their low prices.
The correct answer to number 2 is D) Individual business owners set prices to compete for businesses.
A free market economy is one in which there is little government interference in terms of setting prices. Rather, the "invisble hand" (aka competition) between businesses helps to determine what the actual price will be for the consumers.
The correct answer to number 3 is A)They formed monopolies or trusts.
Monopolies and trusts are when an individual or multiple companies work together to corner a specific market. This results in a drastic decrease of competition, allowing for the monopoly or trust to set whatever price they want for a good or service.