Charles Darwin used fossils as evidence to develop his theory of natural selection. Which event would most likely lead to a change in this theory? Scientists make predictions about the theory of natural selection.
Scientists make new discoveries about fossils.
Scientists explain their observations of natural selection.
Scientists use the same technology Darwin used to study fossils.

i think the answer would be reserve.

because growing process had stoped after 4-5 year

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me