A Test Was Made Of $H _ { 0 } : \mu _ { 1 } = \mu _ { 2 } \text { versus } H _ { 1 } : \mu _ { 1 } < \mu _ { 2 }$

Multiple Choice

A test was made of $H _ { 0 } : \mu _ { 1 } = \mu _ { 2 } \text { versus } H _ { 1 } : \mu _ { 1 } < \mu _ { 2 }$
The sample means were $\bar { x } _ { 1 } = 14$ and $\bar { x } _ { 2 } = 11 \text {, }$ the sample standard deviations were $s _ { 1 } = 8 \text { and } s _ { 2 } = 4$ and the sample sizes were $n _ { 1 } = 12 \text { and } n _ { 2 } = 20$
How many degrees of freedom are there for the test statistic, using the simple method?

A) 12
B) 11
C) 13
D) 10