The given sentence is in active voice. Change the voice of the sentence. Select the correct option from the sentences given in options.

She persuaded him for over a year.

He was persuaded by her for over a year.

The correct passive voice of the sentence She persuaded him for over a year is He was persuaded by her for over a year.

The active voice of the sentence is She persuaded him for over a year. 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 "he" and the main verb is "persuade." The past participle of "persuade" is "persuaded." So, the passive form of the sentence is He was persuaded by her for over a year.

The other options are incorrect because:

• He was being persuaded by her for a year. is also in the passive voice, but the present participle "being" is not necessary.
• He kept being persuaded by her for a year. is in the present perfect tense, which is used to describe an action that has happened in the past but is still relevant to the present. The action of being persuaded happened in the past, so the present perfect tense is not appropriate.
• She was being persuaded by him for over a year. is in the passive voice, but the subject of the sentence is incorrect. The person who was being persuaded is "he," not "she."