Option d is the correct answer. Akbar's popularity was due to his various reforms and policies that he implemented during his reign. He was a visionary ruler who tried to create a harmonious and prosperous empire that transcended the boundaries of religion, caste, language, and region. Some of his notable reforms and policies were: Mansabdari system: This was a system of ranking and salary for the military and civil officers of the Mughal administration. It was based on the principle of merit and loyalty, and it ensured a regular and efficient service from the nobles. Religious policy: Akbar was a tolerant and liberal ruler who respected all faiths and tried to create a harmony among them. He abolished the jizya tax on non-Muslims, allowed freedom of worship, and held regular debates and discussions on religious matters in his Ibadat Khana. He also founded his own religion, called Din-i Ilahi, which was a synthesis of various religious elements. Land Revenue System: Akbar reformed and improved the land revenue system that was initiated by Sher Shah Suri. He appointed Raja Todar Mal as his finance minister, who introduced a uniform system of land measurement called zabti or bandobast. He also devised a system of fixing the revenue demand based on the average yield of land assessed on the basis of the past ten years, called dahsala or dasala. Social reforms: Akbar also introduced some social reforms that aimed at improving the condition of women and the weaker sections of society. He prohibited sati (the burning of a widow) unless she expressly desired it of her own free will.