Select the option that expresses the given sentence in active voice.…

The correct active voice form of the given sentence "The important points were narrated in the class by the teacher" is The teacher narrated the important points in the class.

The passive voice of the sentence is "The important points were narrated in the class by the teacher." This sentence is in the simple past tense, which is used to describe an action that happened in the past. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "important points" and the main verb is "narrate." The past participle of "narrate" is "narrated." So, the passive form of the sentence is "The important points were narrated in the class by the teacher."

The active voice of the sentence is formed by putting the subject of the passive sentence before the verb and removing the word "by." In this case, the subject of the passive sentence is "teacher," and the verb is "narrate." So, the active form of the sentence is "The teacher narrated the important points in the class."

The other options are incorrect because:

• The teacher was narrating important points in the class." This sentence is in the present progressive tense, which is used to describe an action that is happening now but is not finished. However, the action of narrating the important points happened in the past.
• The teacher had narrated the important points in the class." This sentence is in the past perfect tense, which is used to describe an action that happened in the past before another action happened. However, there is no other action mentioned in the sentence.
• In the class, the important points were narrated." This sentence is in the passive voice, but the subject of the sentence is not clear.