What was the Commercial Revolution?

a trade war between European countries following the colonization of the New World
the decrease in global trade between Europe, the Americas, and Africa
an enormous change in the rules of commerce due to the Columbian Exchange
the replacement of colonialism with mercantilism

explanation:

the addition to geographic boundaries that might have  kept the people of the huang river civilization from traveling to far distance region is that they had learned about the other river valley civilizations but feared contact would bring invasion.

hope this .

plz give me brainliest!

the answer is a. harriet tubman was a nurse on the battlefield.

rescuing someone who is in danger. hope this : )