What type of hypothesis indicates that one group's score will be significantly different from another group's score?

The concept of a hypothesis is fundamental in research, particularly in the context of testing statistical differences between groups. An alternative directional hypothesis specifically asserts that there will be a significant difference in a particular direction between two groups. For instance, it posits that one group will have a higher or lower score than the other. This type of hypothesis is often based on prior research or theory that suggests a specific outcome is expected.

In contrast, the alternative nondirectional hypothesis simply states that there will be a difference between the groups but does not specify the direction of that difference (i.e., it doesn't indicate whether one group will score higher or lower than the other). The null hypothesis serves as a baseline assumption that there is no significant difference between groups. Lastly, the term "non-directional hypothesis" is synonymous with the alternative nondirectional hypothesis and indicates that the researcher is open to finding a significant difference in either direction.

Thus, the alternative directional hypothesis is the most precise choice when indicating an expectation of a specific difference in scores between two groups, making it the correct answer.