When Comparing Two Groups with a T-Test, Which Is the Best

Multiple Choice

When comparing two groups with a t-test, which is the best approach?

A) Either test can be used unless the standard deviations differ by a factor of 3 or more, in which case you can only use a two-sample t-test.
B) Either test can be used unless the standard deviations differ by a factor of 3 or more, in which case you can only use a Welch's t-test.
C) Neither test can be used unless the standard deviations differ by less than a factor of 3, in which case you can use a two-sample t-test.
D) Neither test can be used unless the standard deviations differ by less than a factor of 3, in which case you can use a Welch's t-test.