Recall the Application About the Costs Involved in Opening a Dunkinʹ

Recall the Application about the costs involved in opening a Dunkinʹ Donuts shop to answer the
following question(s) .
-Recall the Application. Which of the following prevents Dunkinʹ Donut from being classified as a monopoly?

A) There are many sellers of donuts other than Dunkinʹ Donuts.
B) There are no patents or regulations that prevent entry. All an entrepreneur needs is to pay the franchise fee and the royalties.
C) Donuts are differentiated products that have many close substitutes.
D) All of the above prevent Dunkinʹ Donuts from being classified as a monopoly.