What is the difference between an A$/$B test and a Multi$-$variate test?

Group of answer choices

The critical difference is that A$/$B testing focuses on two variables, while multivariate is $2+$ variables.

Multi$-$variate testing is the same concept as CRO.

A$/$B testing is only one test, and Multi$-$variate is conducting more than one test at a time.

Multi$-$variate testing aggregates all A$/$B test results into one view.