A. Guru Nanak
B. Guru Angad
C. Guru Arjun Dev
D. Guru Gobind Singh
Explanation:
According to Sikh tradition, Gurmukhi (literally, “from the mouth of the Guru”) was invented in the mid-16th century by Angad, the second Sikh Guru (head of the Sikh religion), in order to correct certain inadequacies in the Lahnda script so that sacred literature might be accurately recorded.