Option a is the correct answer. Rag-Govind was written by Mirabai. She was a 16th century Bhakti saint who was devoted to Krishna as her true husband. Rag-Govind is a collection of devotional songs based on the raga Govind, which is a musical mode associated with Krishna. In this book, Mirabai describes the various aspects of Krishna's personality, such as his beauty, his charm, his playfulness, his compassion, his protection, his grace, etc. She also expresses her longing for Krishna's vision and union.