An analyst stated that, all else equal, increasing sample size will decrease both the standard error and

Question:

An analyst stated that, all else equal, increasing sample size will decrease both the standard error and the width of the confidence interval. The analyst's statement is correct in regard to:
A. Both the standard error and the confidence interval
B. The standard error, but incorrect in regard to the confidence interval
C. The confidence interval, but incorrect in regard to the standard error?