How did rockefeller and the standard oil company get around laws that forbade companies in one state from underselling or doing business in other states?

The correct answer is C) they developed the idea of creating trusts.

Rockefeller and the Standard Oil Company got around laws that forbid companies in one state from underselling or doing business in other states because they developed the idea of creating trusts.

From the very beginning, Rockefeller was a successful businessman in the industry of Oil. He started to shipping oil barrels using railroads. His Standard Oil Company was so big and production so high that he could underbid the competitors. And not only that, he got around laws that forbid companies in one state from underselling or doing business in other states because they developed the idea of creating trusts.

The other options of the question were, a) they bribed congressmen to change the law, b) they ignored the law since they were not enforceable, and d) they decided to monopolize the oil business.  

i think it was   tsar alexander ii