The correct answer is C. t-test.
A t-test is a statistical test that is used to compare the means of two groups. It is a parametric test, which means that it assumes that the data are normally distributed. The t-test is a powerful test and can be used to detect small differences between the means of two groups.
A chi-squared test is a statistical test that is used to compare the observed and expected frequencies in a contingency table. It is a non-parametric test, which means that it does not make any assumptions about the distribution of the data. The chi-squared test is a relatively weak test and can only detect large differences between the observed and expected frequencies.
An ANOVA is a statistical test that is used to compare the means of three or more groups. It is a parametric test, which means that it assumes that the data are normally distributed. The ANOVA is a powerful test and can be used to detect small differences between the means of three or more groups.
Regression analysis is a statistical method that is used to determine the relationship between two or more variables. It is a non-parametric test, which means that it does not make any assumptions about the distribution of the data. Regression analysis can be used to predict the value of one variable based on the values of the other variables.
In conclusion, the correct answer to the question “Which statistical test is commonly used to determine if there is a significant difference between the means of two groups?” is C. t-test.