Answer:
E. The sample size is the same for X and Y, and the confidence level used for the interval constructed from X is greater than the confidence level used for the interval constructed from Y
Step-by-step explanation:
Confidence interval formula is given as
CI = \bar{x} \pm z*(\sigma/\sqrt{n})
Here, we can see that the width of confidence interval is z*(\sigma/\sqrt{n}) , which is dependent only on z critical value, standard deviation (sigma) and sample size (n)
This simply entails that either z or n or both are greater for x as compared to y.
Option E is correct answer because x and y can have sample sizes, but if the z critical is greater for x, then the width will be larger.