The correct Active/Passive form of the given sentence is:

☀ The oath will be taken by the newly elected MLAs on Monday.

 Explanation for other options:

☀ The oath will have been taken by the newly elected MLAs on Monday. This option uses the future perfect tense ("will have been taken"), which suggests a completion of the action before a specific point in the future. The original sentence is in the simple future tense, so the correct form should be "The oath will be taken by the newly elected MLAs on Monday."

☀ On Monday, the newly elected MLAs will be taking the Oath. This option changes the structure of the sentence and uses the present continuous tense ("will be taking") in the active voice. While it conveys a similar meaning, it is not the correct passive form of the sentence.

☀ The oath would be taken on Monday by the newly elected MLAs. This option uses "would" which suggests a conditional or hypothetical situation, and it changes the original meaning of the sentence. The correct form should be in the simple future tense, as shown in the first correct option.