The most significant effect of the events described in the above graphic was— a

the exchange of ideas on religion between the old and new worlds

b

a long term decline in the economies of Europe

c

catastrophic reduction of native populations in the New World

d

the introduction of tobacco products into Africa

a

the exchange of ideas on religion between the old and new worlds

a system in which products were made rapidly by machines

although world war i began in 1914, the united states did not join the war until 1917. the additional firepower, resources, and soldiers of the u.s. to tip the balance of the war in favor of the allies. remaining neutral. when war broke out in 1914, the united states had a policy of neutrality.