|Question 21Verbal

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To illustrate Albert Einstein's special theory of relativity, picture two jugglers: one juggling on a steadily moving parade float, the other juggling while standing still on a sidewalk. The laws of physics are identical for both motion relative to each other. But what, Einstein wondered, about the speed of light?
Which choice completes the text so that it conforms to the conventions of Standard English?
jugglers, regardless of there
A
jugglers, regardless of their
B
juggler's, regardless of their
C
jugglers', regardless of they're
D