The effect that the Sherman Antitrust Act had at the end of the 19th century was A) It had little immediate effect because of the vague wording of key points of the law.
It made it illegal to operate monopolies which was in line with the U.S. economic policy of a free market.
The wording of the Act was quite vague however which allowed many monopolies to still continue existing. The Act therefore had little effect at first.
In conclusion, option A is correct.
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