what was the effect of building of new military bases as a result of World War 1? a. With an influx of people from other parts of the nation, new ideas were introduced, challenging local customs. B. Training camps brought in thousands of Soldiers & Sailors who spent their pay locally improving the economy. C. An increase in the number of camps and military bases increase the threat of military action against the area. D. Soldiers who are stationed at training camps to jobs in the local economy, negatively affecting local residents.. D. Soldiers who were stationed at training camps took jobs in the local economy, negatively affecting local residents.