Answer:
I think the right answer is c
They wanted to push in North America because they knew that by gaining control over this continent or at least parts of it would mean a lot to the spanish crown and would also be rewared.
By far the most prominent black entrepreneur of the century of was Charles Clinton Spaulding (1874 – 1952), president of North Carolina Mutual Life Insurance Company in Durham North Carolina. It was the nation's largest black-owned business. That’s my thoughts on it, I could be wrong so check in with others too.
Actually the real answer is the second and first world war pouring money into the us economy for output. If that is not an option it would be the invention of the steam engine and the 1800's locomotive industry.
They were built by the Olmecs