Select the correct passive form of the given sentence.

Khushi wiped down the tables.

The tables were wiped down by Khushi.

The correct passive form of the given sentence is The tables were wiped down by Khushi.

The active voice of the sentence is Khushi wiped down the tables. 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 "Khushi" and the main verb is "wipe." The past participle of "wipe" is "wiped." So, the passive form of the sentence is The tables were wiped down by Khushi.

The other options are incorrect because:

• The tables are being wiped down by Khushi. is in the present progressive tense, which is used to describe an action that is happening now but is not finished. The sentence is describing an action that happened in the past, so the present progressive tense is not appropriate.
• The tables were wiped down. is in the simple past tense, but the present participle "being" is not necessary.
• The tables are wiped down by Khushi. is in the present tense, but the action of Khushi wiping down the tables happened in the past.