Answer with explanation:
Mean of the population having 6"-9" Hatching =38
Standard Deviation =4
Confidence interval of 95% means that 95% of data lie within two standard deviations.
That is data values lie between 38-2×4 to 38 +2×4.
⇒Which is 38-8 to 38+8.
⇒30 to 46.
it is also given that margin of error is 2.5%.
So, the data value will lie between

Mean of beginning value to extreme value of 95% confidence level

So, Sample mean of this observation having 2.5% margin of error = 38
Option D:→ 38