Which form correctly illustrates the heavy emphatic nūn?

Complete Paradigms of the Hollow Yāʾ Verb: Bāʿa–Yabīʿu

• لَيَبِيعَنْ
• لَيَبِيعَنَّ
• لَمْ يَبِعْ
• لَنْ يَبِيعَ