The Gupta empire (320 CE - 550 CE), also known as The Golden Age of India was marked by extensive inventions and discoveries in science, technology, engineering, art, literature, logic, mathematics, astronomy, religion, and philosophy.
1) During this Chandragupta reign a group of nine scholars, also called as the Nine Jewels produced advancements in many academic fields. Within those advancements, they developed a decimal system with a numeral for zero, postulated the theory that the Earth moves round the Sun, and studied solar and lunar eclipses.
2) The correct answer is letter D, Chandra Gupta II. Under his reign Chandragupta II carried the biggest promotion of science, art, philosophy, and religion by the government. During the 4th century, Chandragupta Vikramaditya conquered about twenty one kingdoms, both in and outside India.
3) Chess was first invented by Indians in ancient India and was first played by 4 players This game was known in India nearly 3,000 years ago.