While researching a topic, a student has taken the following notes:
<ul> <li>Two genome studies estimated the divergence date between humans and chimpanzees.</li> <li>Genetic clock A used a slow mutation rate, yielding a divergence date of about 13 million years ago.</li> <li>Genetic clock B used a fast mutation rate, yielding a divergence date of about 6 million years ago.</li> <li>Fossil evidence places the split closer to 7 million years ago.</li> <li>Both methods rely on assumptions about generation length and mutation rate.</li> </ul> The student wants to emphasize that the discrepancy depends on mutation-rate assumptions. Which choice most effectively uses relevant information from the notes to accomplish this goal?Which choice most effectively makes the student's point?
- A
The two estimates differ by about 7 million years.
- B
Both methods rely on assumptions about generation length.
- C
Fossil evidence places the split around 7 million years ago.
- Dcheck_circle
Whereas a slow mutation-rate assumption pushed the human-chimp divergence back to roughly 13 million years ago, a faster rate pulled it forward to about 6 million years ago, with fossil evidence near 7.
Explanation
The goal is that the discrepancy depends on mutation-rate assumption. Choice C names both rates, both estimates, and the fossil reference point. The others omit the dependence.