In the Bhagavad Gita, before the Kurukshetra war began, Lord Krishna revealed his universal form (Vishwaroopa) to Arjuna, showing him the entire cosmos, time, and divine power. This transformative vision gave Arjuna the clarity and spiritual resolve to fulfill his duty as a warrior. The other options describe divine sights from different Hindu traditions but are not the vision that motivated Arjuna in this context.