Question

What segment of the economy was boosted by oil being extracted here?

Answer 1

It was mainly "the automobile industry used the substance to power cars and trucks," that was boosted by oil being extracted here, since gasoline is derived from oil. 

Answer 2

The correct answer is: "The automobile industry used the substance to power cars and trucks".

Oil extraction fostered the emergence of other industries close by. These industries were mostly higher-value added steps within the same production processes, in which the main raw material used as input was oil. The emergence of these oil-related industries near the extraction plants, gave firms the opportunity of decreasing transportation costs and hence, of producing more efficiently to be more competitive in terms of prices.

The automobile industry is a perfect example of a production process in which its first step is oil extraction. This is why car industries were boosted after oil extraction started in the US territory.