The T Value Is Used for Many Tests Instead of the Z

Multiple Choice

The t value is used for many tests instead of the z value because:

A) it is easier to calculate and to interpret.
B) it is more widely known among statisticians.
C) assumptions of the z value are violated if sample size is 30 or less.
D) it is available on statistical software packages.
E) assumptions of the t value are violated if the sample size is 10 or less.