Choose the correct answer

Which of the following forms is indeclinable (مبنی) and does NOT drop its Noon when prefixed with لَمْ?

Conjugating Past Absolute Negation with "Lam" (Active & Passive)

• لَمْ يَفْعُلْنَ
• لَمْ يَفْعُلَا
• لَمْ تَفْعُلِيْ
• لَمْ يَفْعُلُوْا