Que: Which of the following relations is the reflexive relation over the set {1, 2, 3, 4}?

a. {(0,0), (1,1), (2,2), (2,3)}

b. {(1,1), (1,2), (2,2), (3,3), (4,3), (4,4)}

c. {,(1,1), (1,2), (2,1), (2,3), (3,4)}