Which of the following is a correct set of boundary values to test the "Group Size" parameter, as defined by the following statement;

Which of the following is a correct set of boundary values to test the "Group Size" parameter, as defined by the following statement;

"In a reservation system for groups visiting a small museum, the graphical user interface presents a field asking the number of group members. Group size can be anywhere from 2 to 20 visitors"
A . 0,1,8,21,22
B . 0,1,2,3,10,19,20,21,22
C . 2,3,19,20
D . 1,2,20,21

Answer: C