Explanation: From the given options, the word that best completes the sentence, is the corresponding to option B: "We scurried into our theater seats just as the first line of the prologue was spoken, and I breathed a sigh of relief that we'd made it just in time," because the prologue is the introductory section or the first part of a literary, dramatic (a play), or musical work.
Answer: The Miller-Urey experiment provided the first evidence that organic molecules needed for life could be formed from inorganic components. Some scientists support the RNA world hypothesis, which suggests that the first life was self-replicating RNA.
