Final answer:
Option C, "Greenfield, the director of the CDMC, considers the results significant, given that they occurred after only five days," is the sentence from Text 1 that best supports the correct answer to Part A.
Step-by-step explanation:
The sentence from Text 1 that best supports the correct answer to Part A is option C, which states, "Greenfield, the director of the CDMC, considers the results significant, given that they occurred after only five days." This sentence supports the correct answer because it mentions the director's opinion about the results, indicating that they are noteworthy and meaningful. It also highlights the short duration of the study, emphasizing the significance of the results being achieved in just five days.