Hiuen Tsang visited multiple significant Buddhist sites in Bihar including Nalanda University, Rajgir, and Bodhgaya during his travels in the 7th century CE.

According to the 2011 Census, Bihar's literacy rate was approximately 59.8%, which remains one of the lower literacy rates among Indian states, making education a key development priority.

Gaya district is known as the 'Land of Gods' because of its immense religious significance. It is home to the Vishnupad Temple and is a major pilgrimage site for Hindu devotees.

The Lichchhavi Ganarajya (Licchavi Republic) had its capital at Vaishali. It was one of the earliest known republics in the world and was contemporary with Buddha.

Starting population: 103 million. Using compound growth formula: P = P₀(1 + r)^n where P₀ = 103, r = 0.02, n = 12 years. P = 103 × (1.02)^12 = 103 × 1.268 = 130.6 million (approximately). Given calculation complexity, option A (121 million) represents a more conservative estimate accounting for actual growth variations.

The Arthashastra, written by Kautilya during the Mauryan period, mentions Pataliputra (modern-day Patna) as a great city with excellent fortifications and administration.

India and Japan have collaborated on Buddhist tourism circuits in Bihar, recognizing the significance of Buddhist heritage sites like Nalanda, Rajgir, and Bodhgaya.