Final answer:
The correct answer is option B, analysis of variance (ANOVA).The correct answer to determine if a relationship exists between four groups with equal sample sizes and an interval-level dependent variable is option B.
Step-by-step explanation:
A one-way ANOVA is used when you want to test the differences between more than two groups, as is the case with the student's scenario of having four groups to compare. This statistical method assesses whether the means of several independent groups are statistically significantly different from each another. For ANOVA to be applicable, the samples from the groups should meet certain assumptions, such as being randomly selected, from populations with equal variances, and normally distributed.
The test involves comparing the variance (variability) between the groups with the variance within the groups. If the ANOVA test shows a statistically significant difference, this suggests that at least one group mean is different from the others, hence indicating a relationship between the groups and the dependent variable.