Answer:
John D. Rockefeller. Rockefeller made his fortune by revolutionizing the oil industry.
That's a D from me, to culminate would be to grow, build, culminate
The best option from the list would be that "<span>b. The United States began to build up its military and to stockpile weapons," since this was part of the inevitable "Arms Race" that took place between the US and the USSR. </span>