Concept:Passive voice keeps the tense of the active sentence while making the object the new subject.Explanation:The original sentence is in the simple past tense: “gave”.In passive voice, the simple past of “give” becomes “were given”.The subject “the pupils” is plural, so we use “were”.The object “their marked books” remains as the thing given.The correct passive form is therefore: “The pupils were given their marked books by the teacher.”Answer:D. The pupils were given their marked books by the teacher.