Because we estimate the standard deviation of the sample proportion using the standard error for confidence interval estimation, we must use a t distribution critical value t* when calculating the margin of error for the confidence interval.
This statement is not accurate.
When estimating the standard deviation of the sample proportion using the standard error for confidence interval estimation, we use the normal distribution critical value (z*) rather than the t-distribution critical value (t*). A t-distribution critical value is used when estimating the margin of error for confidence intervals for sample means, not sample proportions.