One Experimental Observation That Demonstrates Einstein's Ideas on the Relativity

One experimental observation that demonstrates Einstein's ideas on the relativity of time, is

A) electromagnetic waves from the early stages of the development of the universe have slower rates of vibration.
B) rapidly- rotating neutron stars spin more slowly than they would if they weren't moving rapidly away from us.
C) muons "live" longer when moving rapidly than they do when they are at rest.
D) a laser beam emitted from an orbiting satellite is observed from Earth.
E) the recent discovery of very fast- moving particles known as tachyons.