Respuesta :
I’d say “when the email goes done, every one of the teachers holds their breath anxiously” because every one is equivalent to singular form so teacher wouldn’t take and S. Plus holds is conjugated with he/she so it doesn’t make sense if it’s plural. Hope that helps :)
err... that one is hard. im thinking its the second option cause the rest dont seem to have any error, but the sentence doesnt make much sense. id go for the second option "When e-mail goes down, every one of the teachers holds their breath anxiously." so sorry if im wrong, update me when u know the correct answer! (: