【单选题】Consider an object on a rotating disk a distance r from its center, held in place on the disk by static friction. Which of the following statements is NOT true concerning this object?
A.
If the angular speed is constant, the object has a zero acceleration.
B.
The object has a tangential acceleration only if the disk has an angular acceleration.
C.
The object always has a centripetal acceleration except when the angular speed is zero.
D.
If the angular speed is constant, the speed of object is also constant.