Help the science historian finish her dramatic documentary script by selecting the grammatically correct option.

"For decades, the professor's groundbreaking theory on quantum mechanics _____ by the mainstream scientific community."

The correct answer is was simply not understood.

A crucial rule of the "get-passive" is that it cannot be used with stative verbs (verbs that describe states rather than actions, such as understand, know, believe, or own).

Because "understand" is a stative verb, we must use the standard "be-passive" (was not understood).