The Delhi Sultanate era was marked by a notable confluence of intellectual and cultural developments, with scholars contributing significantly to the historiography, literature, and socio-political thought of their time. Among these scholars, the Persian historian Ziauddin Barani is particularly renowned. Which of the following aspects best characterizes Barani's historical narrative in his work "Tarikh-i-Firoz Shahi," and how did his perspectives influence the understanding of governance and morality during the period?

a) Emphasis on Sufism and spiritual guidance in administration: Barani argued that the Sultanate's success depended on Sufi principles guiding the rulers' actions, as seen in his alignment of political events with Sufi teachings.
b) Detailed chronological account of battles and conquests: His works meticulously documented military campaigns and territorial expansions, similar to other contemporary historians, highlighting the bravery and strategies of the Sultans.
c) Moral and ethical analysis of political authority: Barani's narrative was distinct in its evaluation of rulers based on their adherence to Islamic ethical standards, emphasizing the role of just and moral governance in statecraft. His critiques of rulers' behaviors and policies profoundly influenced the Islamic political thought of his time. 
d) Promotion of agricultural and economic reforms: His chronicles extensively discussed the Sultanate's economic policies, particularly agricultural reforms and market regulations, advocating for economic stability as the foundation of a strong state.