One of the main reasons john d. rockefeller was able to succeed in the oil industry was because he
a) encouraged competition.
b) treated his competitors fairly.
c) combined vertical and horizontal integration.
d) urged government regulation of the oil industry.

to protect the united states' role as a world leader, president truman wanted to prevent the soviet union from spreading communism beyond its post-world war ii boundaries. he declared that the united states must assist any nations struggling to prevent a communist takeover.

the enslavement and death of yeet