What happened before the united states could begin building a canal in panama?

Ireally need on this homework! if you get it right so much if not its fine < 3 ! (i have no points so sorry its only 10)i didnt mean to put it on social studies sorry!

Between 1518 and 1548, spanish conquistadores conquered most of the new world, motivated by the a) desire for scientific knowledge. b)  to urge to claim more territory for spain. c) belief that an all-water western route to the orient existed. d) desire to advance national glory, serve god, and seek personal wealth.

How is the uk’s government is solving the air pollution problem?