Choose the incorrect statements from the following:
(I) If object changes its position with respect to its surroundings in a given time, it is said to be in motion.
(II) If there is no change in the position of an object with respect to its surroundings in a given time, it is said to be at rest.
(III) If a body in translatory motion moves along a straight line then the motion is called rectilinear motion.
(IV) Average speed is defined as "The distance travelled by a body in a given time".