The statement which violates the First Law of Motion is: C. The speed of an object changes even though no forces act on the object.
Newton's First Law of Motion is also referred to as Law of Inertia and it states that an object (physical body) in motion would continue in its state of motion at continuous velocity (in the same speed and direction) or if at rest, it will remain at rest unless it is acted upon by an external force.
This ultimately implies that, it describes the tendency of an object (physical body) to continue in its state of motion or remain at rest, unless when acted upon by an external force.
In conclusion, we can deduce that a violation of the First Law of Motion is the speed of an object (physical body) changes even though no forces act on the object.
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