Which series correctly shows Aḥmad’s three ordinary cases?

Diptote Causes — Verb Patterns and Their Conditions

• Aḥmadu, Aḥmada, Aḥmada
• Aḥmadu in all cases
• Fatḥa, kasra, ḍamma
• Aḥmadun, Aḥmadan, Aḥmadin