Explanation:

- The Vedic Civilisation is traditionally believed to have flourished along the river Saraswati.

- Saraswati is often mentioned in the ancient Indian texts, including the Rigveda, as a mighty river.

- In modern research, the existence of Saraswati is often linked to the Ghaggar-Hakra river system.

- Other rivers like Tapi, Narmada, and Godavari are significant in Indian history but not linked with the Vedic Civilisation.

- Tapi and Narmada flow in central India, while Godavari flows in southern India.

Therefore, the correct answer is:

- Option 3: Saraswati