Option b is the correct answer. Babur was the first Timurid ruler who assumed the title of Padshah after his conquest of Kabul (1507). He asserted his superiority over the Chaghtai mughals and other Timurid rulers. By assuming the title of Padshah, Babur claimed to be the rightful heir to the Timurid Empire. The title of Padshah is a Persian word that means "emperor" or "king".