The graph represents a system of inequalities for the scenario where x is the number of confirmed parties on a tour and y is the number of required copies of the itinerary. which constraint could be part of this system of equations?
a. at least 2 copies are required per tour.
b. more than 2 copies are required per tour.
c. the number of confirmed parties must be at least double the number of required copies.
d. the number of confirmed parties must be no more than double the number of required copies.