Respuesta :
This is a matter of hypothesis testing.
Null hypothesis: no difference between the mean weights of the population of two neighboring districts
It is important to know the decision rule. At which condition do we reject or accept null hypothesis.
Example is If p value < significance level, reject null hypothesis.
We then can use the z-statistic. It's best to choose the higher confidence level to account for other results, bias and errors thus, we choose either B or C to be confident in that range of our values.
Null hypothesis: no difference between the mean weights of the population of two neighboring districts
It is important to know the decision rule. At which condition do we reject or accept null hypothesis.
Example is If p value < significance level, reject null hypothesis.
We then can use the z-statistic. It's best to choose the higher confidence level to account for other results, bias and errors thus, we choose either B or C to be confident in that range of our values.

The statement that is true is; A. The null hypothesis must be accepted if we choose the 68% confidence level. .
How to state the hypothesis?
We are given;
Sample mean difference; x'₁ - x'₂ = 12 kg
We are also see that the standard deviation of the distribution of the difference between sample means is 9 kilograms.
This means that the difference in the above is much and we can therefore conclude that the null hypothesis must be rejected if we choose the 68% confidence level. The reason being that there is a noticeable difference.
Read more about Hypothesis at; https://brainly.com/question/15980493
#SPJ5