The correct answer is option 1: Indo-Greek coins.

Indo-Greek coins were the earliest coins in India to bear the names and busts of rulers. These coins were issued by the Indo-Greek kings who ruled over parts of northwest India during the 2nd century BC to the 1st century AD.

Option 2: Kushana coins were issued by the Kushan Empire, which ruled over a large part of northern India from the 1st to 3rd centuries AD. While Kushana coins did feature the busts of rulers, they were not the earliest coins to do so in India.

Option 3: Gupta coins were issued by the Gupta Empire, which ruled over a significant part of northern India from the 4th to 6th centuries AD. Gupta coins did feature the names and busts of rulers, but they were also not the earliest coins to do so.

Option 4: Punch-marked coins were an earlier form of coinage used in India from around the 6th century BC to the 2nd century BC. These coins were typically made of silver and featured various symbols and markings, but they did not bear the names and busts of rulers like the Indo-Greek coins.

In conclusion