Answer:
Answer: B. Year 2
Explanation: During a drought, the proportion of larger, harder seeds tends to increase. Only finches with deep beaks are able to crack these seeds. Finches with larger beaks are more likely to survive and successfully reproduce. In year 2, beak depth increased sharply, indicating drought. However, average beak depth did not increase in years 1, 3, 4 or 5. This suggests that these were years of average or excessive rain.