Final answer:
The first month of the Muslim Calendar is Muharram, a significant time that signals the start of the Islamic lunar year.
Step-by-step explanation:
The first month of the Muslim Calendar is c) Muharram. This month holds significant religious importance for Muslims as it marks the beginning of the Islamic lunar calendar. Muharram is followed by the month of Safar, and then comes Rabi' al-awwal, and so on, until the last month, Dhu al-Hijjah, during which the Hajj is performed. The month of Ramadan is also crucial for Muslims, as it is the month of fasting and spiritual reflection, commemorating the period when the Quran was first revealed to the Prophet Muhammad.