Final answer:
An object with a constant velocity can either be stationary or traveling with a constant speed in a straight line, which is referred to as uniform motion.
Step-by-step explanation:
If an object has a constant velocity, its possible state is B) Stationary or traveling with constant velocity. When an object's velocity is constant, it means that the speed and direction of the object are not changing. This includes situations where the object is not moving at all (stationary), or it is moving in a straight line at a constant speed (uniform motion).
On the other hand, 'accelerating' and 'decelerating' imply a change in velocity over time, whether an increase or a decrease in speed respectively. 'Oscillating' refers to an object that is moving back and forth in a regular pattern, which again implies changes in velocity over time. Therefore, these states are not compatible with an object having a constant velocity.
It's important to clarify that motion at a constant velocity or uniform motion means that the position of the object is changing at the same rate, without fluctuations in speed or changes in direction.