When the net force on an object is zero, the object is either at rest or moving at a constant velocity. Therefore, the correct statement from the given options would be:
The object is at rest.
However, it's important to note that the phrase "The object is at rest" is not complete because an object can also continue to move at a constant speed in a straight line when the net force is zero. If you are to choose strictly from the provided options without considering constant motion, "The object is at rest" is the most fitting choice.