Confidence interval precision: We know that narrower confidence intervals give us a more precise estimate of the true population proportion. Which of the following could we do to produce higher precision in our estimates of the population proportion?

o a. We can select a higher confidence level and decrease the sample size
o b. We can select a higher confidence level and increase the sample size
ⓔ C. We can select a lower confidence level and increase the sample size
d. We can select a lower confidence level and decrease the sample size