Would the following sentence, by the strictest standards, be considered correct by a linguist?

The tuna had been being eaten.
OPTIONS:
- unacceptable
- acceptable
acceptable
Skulle följande mening, med strängaste mått mätt, anses vara riktig av en språkforskare? Tonfisken hade blivit uppäten. ALTERNATIV: - oacceptabelt - godtagbart
Would the following sentence, measured by the strictest measure, be considered correct by a linguist? The tuna had been eaten. ALTERNATIVES: - unacceptable - acceptable
kan godtas
Acceptable