Answer:
B. Time, length, and mass
Step-by-step explanation:
Got it right on the quiz.
"Einstein found that what you measure for length, time, and mass depends on your motion relative to a chosen frame of reference. Everything is in motion. ... All motion is relative to a chosen frame of reference. That is what the word "relativity'' means in Einstein's Relativity theories."
Einstein found that time, length, and mass are relative.