Aman standing on a bus remains still when the bus is at rest. when the bus moves forward and then slows down the man continues moving forward at the original speed. this is an example of the effect of
a. gravity.
b. weight.
c. velocity.
d. inertia.

Matter has a property that makes it have a tendency to remain at its original motion. We call this property inertia. This is also the reason why a man standing on the bus continues moving forward despite the bus slowing down. He will have the tendency to go to the same direction prior to the change. Thus, the answer is D: inertia.