Read the passage carefully and answer Q.
A dancer demonstrating dance steps along a straight line. The position time graph is given below.
The average velocity of the dancer during time interval between t = 4.5 s to t = 9 s is
(A) 1 ms-1
(B) -1.33 ms-1
(C) 2.75 ms-1
(D) - 0.89 ms-1.