The correct answer is option 1: 261 BC. The Kalinga War was a significant battle that took place in ancient India. It was fought between the Mauryan Empire led by Emperor Ashoka and the Kalinga kingdom in present-day Odisha. The war occurred in the year 261 BC. It was a brutal and destructive conflict, causing immense loss of life and devastation. The war had a profound impact on Emperor Ashoka, who was deeply affected by the suffering he witnessed and eventually led to his conversion to Buddhism and his commitment to non-violence. The Kalinga War is often seen as a turning point in Indian history, leading to Ashoka`s transformation and the spread of Buddhism throughout the region.