The correct answer is: Buddhism.
Vaishali was an important city in the ancient Indian subcontinent. It was one of the capitals of the Vajji confederacy, and it was also the site of the first Buddhist council. The city is mentioned in many Buddhist texts, and it is considered to be one of the four holy cities of Buddhism.
Vaishali is located in the present-day state of Bihar, India. It is about 100 kilometers from Patna, the capital of Bihar. The city is situated on the banks of the Ganges River.
Vaishali was founded in the 6th century BCE by the king of the Videha kingdom. The city was originally called Vishala, which means “great.” Vaishali became an important center of trade and commerce. It was also a center of learning and culture.
In the 6th century BCE, the Buddha visited Vaishali and delivered many sermons there. The city was also the site of the first Buddhist council, which was held after the Buddha’s death. The council was convened to discuss and codify the Buddha’s teachings.
Vaishali continued to be an important city until the 6th century CE. After that, the city declined in importance. However, it is still a holy city for Buddhists, and it is a popular tourist destination.
The other options are incorrect because they are not associated with Vaishali. Hinduism is the oldest religion in the world, and it is the majority religion in India. Jainism is an ancient Indian religion that emphasizes non-violence and asceticism. Sikhism is a monotheistic religion that was founded in the 15th century CE.