Aryabhatta and Kalidasa were both well-known figures in ancient India. Aryabhatta was an astronomer and mathematician, while Kalidasa was a renowned poet and playwright. According to historical records, both of them served in the court of the Gupta Empire. The Gupta Empire was a powerful dynasty that ruled over a significant portion of northern India from the 4th to the 6th centuries CE. When it comes to identifying the specific Gupta Emperor in whose court Aryabhatta and Kalidasa served, we need to consider the given options. The correct answer is option 2, Chandra Gupta II. Chandra Gupta II, also known as Chandra Gupta Vikramaditya, was a notable ruler of the Gupta Empire and a patron of arts and sciences. Therefore, Aryabhatta and Kalidasa were in the court of Chandra Gupta II.