Given a quadrilateral with sides 4 cm, 5 cm, 12 cm, and y (where the length of y is unknown), the length of y must be between 1 cm and 18 cm.
Which of the following is a counterexample to this conjecture?
A. y = 21.5 cm
B. y = 20 cm
C. y = 22 cm
D. y = 24 cm