Why did the indigenous population of central america decline with the arrival of europeans?
a. they died fighting the spanish.
b. european diseases killed a large portion of the population.
c. they emigrated to mexico.
d. they emigrated to south america.

Many of the indigenous population of Central America declined with the arrival of Europeans as a) they died fighting the Spanish. Many of the indigenous groups which inhabited what is now modern-day Central America waged many battles with the Spanish settlers and this greatly decreased the population of Natives living in the various nations.