According to the given excerpt, the sentence that best summarizes the Ida Tarbell's assessment of standard oil include option C: The company was ruthless in its drive to eliminate competition.
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What is the assessment of Standard Oil?</h3>
John D. Rockefeller once decided to combined all its companies into one entity in order to reduce the competition in the market and create monopoly this will leads to control the prices in his hands.
Standard Oil is never great because it abuses its power and took advantage of the weakness of its competitors.
Therefore, in 1911, the court ordered to separate the illegal monopoly into 34 companies.
Therefore, correct option is C.
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