Lylah created an app, and she recently updated the app. She randomly samples a group of users to estimate what percentage of all users are using the updated version.
What type of statical test used in this case?
A. A paired t-interval for the mean difference
B. A z-test for a proportion
C. A t-test for a mean
D. A t-interval for a mean
E. A z-interval for a proportion
