The correct answer is option 1 - Battle of Wandiwash. This battle was fought between the British East India Company and the French East India Company in 1760. It proved to be a decisive victory for the British, as it marked the end of French influence in India.
Option 2 - Battle of Assaye, was a significant battle fought between the British East India Company and the Maratha Empire in 1803. While it was an important victory for the British, it did not directly impact the Anglo-French rivalry in India.
Option 3 - Battle of Chillianwala, was a battle fought between the British East India Company and the Sikh Empire in 1849. It was not a part of the Anglo-French rivalry in India.
Option 4 - Battle of Seringapatam, was a battle fought between the British East India Company and the Kingdom of Mysore in 1799. While it greatly weakened the Mysore Kingdom, it did not directly impact the Anglo-French rivalry in India.
Therefore, the correct and decisive battle in the Anglo-French rivalry in India was the Battle of Wandiwash.