Answer:
I'd put b or c I don't really know though
Step-by-step explanation:
Horses were one of the first things traded in the Columbian exchange. They were used for a variety of reasons and really affected life in the Americas. Horses allowed Native Americans to travel to find food and other supplies. Horses also helped strengthen military power. Horses were not the only animals making a large impact on the Americas. However, horses did make working more efficient. Horses also made travelling easier and faster.