What Is Rivalry Among Existing Competitors

What is rivalry among existing competitors?

A) the ability of buyers to affect the price they must pay for an item
B) the suppliers' ability to influence the prices they charge for supplies (including materials, labor, and services)
C) high when it is easy for new competitors to enter a market and low when there are significant entry barriers to joining a market
D) high when competition is fierce in a market and low when competitors are more complacent