Ibrahim Adil Shah, the third option, was a ruler of the Adil Shahi dynasty in Bijapur, India during the late 16th century. He was known for his belief in secularism and his efforts to foster peaceful relations between Hindus and Muslims in his kingdom. As a result, he was given the title ‘Jagadguru’, which means `world teacher` in Sanskrit, reflecting his image as a unifying figure who did not discriminate based on religion. Therefore, this title was not simply bestowed by his Muslim subjects, but by the people of all faiths in his kingdom.

Comparatively, the other options such as Husain Shah, Zain-ul-Abidin, and Mahmud II were also Muslim rulers but they do not hold the same recognition for their secular beliefs as Ibrahim Adil Shah. Husain Shah and Zain-ul-Abidin led different Sultanates in India during different time periods, while Mahmud II was an Ottoman Sultan. Despite their respective contributions, none of them were referred to as ‘Jagadguru’ due to secular beliefs, making option 3 the correct answer.