Option a is the correct answer. The Satavahana dynasty, which ruled during the ancient period in India, initially established their capital at Pratisthan, also known as Paithan, located along the banks of the Godavari River in present-day Maharashtra. This location offered strategic advantages due to its proximity to a major river, facilitating trade and communication. The fertile lands around the Godavari provided agricultural resources to support the growing kingdom. Additionally, being situated in the Deccan region allowed them to maintain control over important trade routes that connected northern and southern India. As the dynasty expanded its territories and influence, the capital was eventually shifted to Amaravati, which had its own strategic significance.