Option b is the correct answer. Alauddin Khilji, a Sultan of Delhi, adopted the title "Sikandar-i-Sani," which translates to "Alexander the Second." This title was a reflection of his ambitious and imperialistic nature. Alauddin aimed to expand his empire and dominance, similar to the conquests of Alexander the Great. He sought to establish his rule on a vast scale and to establish Delhi as the "Dar-ul-Khilafa," symbolizing his operation for a caliphate-like authority.