Which three antibiotic classes among those we studied are fully synthetic $($not known to be made by living organisms$)?$ NOTE: Please enter your three answers in

ALPHABETICAL ORDER! The three antibiotic classes are

$,$ and $$ Abbreviations are fine as long as they're unambiguous and it's clear what you mean. Please use names of CLASSES, not individual antibiotics $($e$.$g$.,$ aminoglycosides not kanamycin$--$that isn't one of the answers, by the way!$).$