To determine whether the means of two populations are equal,

a. a t test must be performed.
b. an analysis of variance must be performed.
c. either a t test or an analysis of variance can be performed.
d. a chi-square test must be performed.

The correct option is C. either a t test or an analysis of variance can be performed.

Step-by-step explanation:

Consider the provided information.

The t-test, is used for whether the means of two groups are equal or not. The assumption for the test is that both groups are sampled from normal distributions with equal variances. Analysis of Variance (ANOVA) is a statistical method evaluating variations between two or more methods. ANOVA is used in a study to analyze the gaps between group methods.ANOVA is used not for specific differences between means, but for general testing.The chi-squared test is often used to evaluate whether there was a significant difference in one or more groups between the predicted frequencies and the observed frequencies.

Hence, Either a t test or an analysis of variance can be performed to determine whether the means of two population are equal.

Therefore, the correct option is C. either a t test or an analysis of variance can be performed.