At a stop on «أَعْبُدُ», what happens to the final dāl?

Al-Kāfirūn and An-Naṣr: Applied Madd, Idghām, Ghunnah and Waqf

• Dāl becomes sākin and requires qalqalah
• Its ḍammah remains pronounced
• Dāl merges into mīm
• Dāl undergoes ikhfāʾ