Which is the BEST example of cultural diffusion?

This term refers to the number of people per unit area (usually a kilometer or a mile). this could refer to the number of people per square mile in a city, a county, a province, a state, or a nation.

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.

During the period from 1865 to 1898 how did the political/economic elite contain the demands of farmers and laborers for economic justice