In ancient india who were responsible for fending off intruders?

In ancient India, the Kshatriyas were responsible for fending off intruders.

History has recorded that the Indian subcontinent was vulnerable to invasions and intrusions. According to the class system prevalent in ancient India, the 'Kshatriyas' (simply the warriors), were responsible for protecting the society from any intrusions and invasions.

They waged armies, collected taxes, looked after the governance and administration, run the judicial system, and fought for the protection of their lands and people from other classes.

letter d is correct.

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