During the Age of the Buddha in Indian History, the Kshatriyas had a distinct identity. The Kshatriyas were one of the four varnas or social classes in ancient India, and they held the role of warriors and rulers.

Option 1: Age of the Buddha - During this period, around 6th to 5th century BCE, the Kshatriyas were recognized as a distinct social group with their own specific responsibilities and privileges.

Option 2: Maurya period - Although the Maurya Empire, which existed from 322 BCE to 185 BCE, was important in Indian history, it did not specifically contribute to the distinct identity of the Kshatriyas.

Option 3: Post-Maurya age - This period, following the decline of the Maurya Empire, did not significantly impact the distinct identity of the Kshatriyas.

Option 4: Gupta period - The Gupta Empire, which lasted from 320 CE to 550 CE, did not particularly contribute to the distinct identity of the Kshatriyas.

Overall, the Age of the Buddha is the correct answer as it was during this period that the Kshatriyas had a distinct identity.