I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "Muawiyah also encouraged peaceful coexistence with the Christian communities of Syria, granting his reign with "peace and prosperity for Christians and Arabs alike", and one of his closest advisers was Sarjun, the father of John of Damascus. At the same time, he waged unceasing war against the Byzantine Roman Empire. During his reign, Rhodes and Crete were occupied, and several assaults were launched against Constantinople. After their failure, and faced with a large-scale Christian uprising in the form of the Mardaites, Muawiyah concluded a peace with Byzantium. Muawiyah also oversaw military expansion in North Africa (the foundation of Kairouan) and in Central Asia (the conquest of Kabul, Bukhara, and Samarkand)."? 

How did Muawiyah oversee military expansion in Asia?