The correct option is C Preached personal devotion of God as a means of salvation
Nayanars and Alvars saints led the bhakti movement in south India. They preached ardent love of Shiva (by Nayanars) or Vishnu(by Alvars) as the path of salvation. They were sharply critical of Buddhists and Jainas. They were against the rigidity of rituals followed by the people. They stressed on devotion and love.