The correct option is D Disbelief in penance
Guru Nanak preached his followers to submit to God’s command. According to Guruji, one who submits to Hukam is spiritually inclined towards him. Some of the Hukams that Guru Nanak Ji considered important were- Recitation of Nam; self surrender; importance of Guru; faith in theory of Karma; belief in brotherhood; emphasis on morality; Sach Kand; disbelief in penance, condemnation of caste and condemnation of rituals.