Explanation:

- Option 1: Lothal

- Lothal is an archaeological site in Gujarat, India.

- It was part of the Indus Valley Civilization and known for its dockyard.

- It was a significant port but not specific to trading with Romans.

- Option 2: Badami

- Badami is known for its rock-cut caves and is in Karnataka.

- It was the capital of the Chalukyas.

- Not known as a fishing colony or major trading port with Romans.

- Option 3: Arikamedu

- Arikamedu is an ancient site near Pondicherry.

- It was a significant port for Indo-Roman trade.

- Consistent with its role as a Greco-Roman trading port.

- This is the correct answer.

- Option 4: Tulapurushandana

- There is no known historical site by this name.

- Likely doesn't relate to ancient trading ports.