Angelica surveyed 150 people in the 20-29 age group and 150 people in the 30-39 age group about whether or not they were vegetarian. She wants to estimate the difference between the percentage of people in each group who are vegetarian.
What type of statical test used in this case?
A. A two-sample z-test for the difference of proportions
B. A χ2 goodness of fit test
C. A paired t-test for the mean difference
D. A two-sample z-interval for the difference of proportions
E. A two-sample t-test for the difference of means