A plot of angular displacement θ versus time t for a rotating wheel is a straight line passing through the origin. Which one of the following statements is correct about the motion?
a) Angular velocity increases uniformly and angular acceleration is positive.
b) Angular acceleration is constant and equal to the slope of the graph, therefore angular velocity increases linearly with time.
c) Angular velocity is constant and angular acceleration is zero.
d) Both angular velocity and angular acceleration are zero.