In Hypothesis Testing, the Area of the Curve in Which

In hypothesis testing, the area of the curve in which it is unlikely a researcher will obtain means is called the rejection region (or region of unlikely values) . What conclusions are drawn when obtained values fall in the rejection region?

A) The experiment was unsuccessful and needs to be redesigned
B) Null hypothesis is rejected; there are differences between groups
C) Null hypothesis is rejected; there are no statistically significant differences between groups
D) Null hypothesis is accepted; there are no statistically significant differences between groups