A researcher selects a sample from a population with a mean of m = 40 and administers a treatment to the individuals in the sample. If the treatment is expected to decrease scores, which of the...

A researcher selects a sample from a population with a mean of
m
= 40 and administers a treatment to the individuals in the sample. If the treatment is expected to decrease scores, which of the following is the correct statement of the null hypothesis for a one-tailed test?​

a. m
<>

b. m

40

​c.
m
> 40

d. m
>
40