Sir Isaac Newton was among the first to observe the movement of objects and express those observations as laws. According to Newton's law of inertia, a body

a. in variable motion will remain in motion unless its state of matter changes.

b. with no kinetic energy will remain along a path with a constant radius.

c. with a variable potential energy will remain with a constant, nonzero acceleration.

d. in uniform motion will remain in motion unless it is acted upon by an outside force ​