Final answer:
In uniform circular motion, velocity is always tangential, and acceleration, called centripetal acceleration, is always directed radially inward towards the center of the circular path.
Step-by-step explanation:
The directions of velocity and acceleration for an object in uniform circular motion are quite specific. The velocity of the object is always tangent to the circular path, while the acceleration, known as centripetal acceleration, is directed radially inward towards the center of the circle. This is because the velocity vector changes direction constantly, even if its magnitude remains constant, thus requiring an inward net force to cause this directional change, which is realized by the centripetal acceleration.
In summary, option (b) 'Velocity is tangential, and acceleration is radially inward' is correct. This is in line with the centripetal force requirement for an object to maintain its circular path. The tangential velocity is always perpendicular to the radius of the circular path, ensuring motion along the circular path, while the centripetal acceleration ensures the object is constantly changing direction towards the center.