Given the velocity versus time graph of an object.
From the graph, the velocity of object A is constant as the line representing its velocity is horizontal. The velocity of object a is decreasing with time. That is, object B is decelerating.
From the graph, at t=5 s the value of the instantaneous velocity of object A is 0 m/s.
And the value of the instantaneous velocity of object B is the same throughout the graph. And the value is 4 m/s.
Thus the value of the instantaneous velocity of object B is greater than that of object A.
Thus the correct answer is B has the greater value