<span>When examining how Rockefeller became successful, notice that he owned absolutely everything regarding the production and transportation. This means that the answer is C) Combined vertical and horizontal integration. He became a monopoly owner meaning he owned everything regarding the production of oil and didn't rely on anyone.</span><span />
In reference, <span>The Encyclopædia Britannica defines "political machine" as, "in U.S. politics, a party organization, headed by a single boss or small autocratic group, that commands enough votes to maintain political and administrative control of a city, county, or state".</span>
<span>SO: It's purpose primarily serves to gain and maintain political and administrative control of city/county/state, none the less the population.</span>
