Suppose you are calculating a 95% confidence interval for the proportion of all students at your school who have ever taken piano lessons. You survey 100 students and find that 60% of them had taken piano lessons in the past. From this, you determine your 95% confidence interval. Which of these individual changes in your summary statistics (without changing anything else) would get you a narrower interval? (Choose all that apply.) 

A. A larger sample size 

B. A smaller sample size 

C. A larger sample proportion 

D. A larger confidence level 

E. A smaller confidence level