Two Independent Samples of Sizes 50 and 50 Are Randomly $\mu _ { 1 } - \mu _ { 2 }$

Multiple Choice

Two independent samples of sizes 50 and 50 are randomly selected from two populations to test the difference between the population means, $\mu _ { 1 } - \mu _ { 2 }$
) The sampling distribution of the sample mean difference $\bar { x } _ { 1 } - \bar { x } _ { 2 }$
Is:

A) normally distributed
B) approximately normal
C) t - distributed with 98 degrees of freedom
D) chi-squared distributed with 99 degrees of freedom