A Real Experiment, Analogous to the "Twin Paradox," Has Actually

Multiple Choice

A real experiment, analogous to the "twin paradox," has actually been done in order to check the predictions of Einstein's relativity. In the experiment,

A) two kilograms oscillated on springs, one of them in on Earth and the other in a space satellite.
B) a human took a trip in a space satellite, while a second human stayed on Earth.
C) a mouse went on a jet airplane trip and returned, while a second mouse stayed on the ground.
D) a mass took a trip in a jet plane, while a second identical mass stayed on the ground.
E) an atomic clock took a trip on a jet plane, while an identical clock stayed on the ground.