Which of the Following Expressions Are True About a Large-Sample $\mu$

Multiple Choice

Which of the following expressions are true about a large-sample upper confidence bound for the population mean $\mu$ ?

A) $\mu < \bar { x } - z _ { \alpha / 2 } \cdot 5 \sqrt { n }$
B) $\mu < \bar { x } + z _ { \alpha / 2 } \cdot 5\sqrt { n }$
C) $\mu < \bar { x } - z _ {\alpha } \cdot 5 \sqrt { n }$
D) $\mu < \bar { x } + z _ { \alpha } \cdot 5 - \sqrt { n }$
E) None of the above statements are true.