Kautilya's theory of Rajamandala belongs to:

The correct answer is Foreign Policy and Inter -state relation

Key Points

• Interstate relations and foreign policy find a prominent place in Kautilya’s Arthashastra.
• He has tried to explain the dynamics of interstate relations through his mandala theory.
• According to the Rajamandala hypothesis, there are four main categories of states:

1. Vijigishu, who aspires to rule the globe,
2. Ari, a rival king whose domain borders Vijigishu,
3. Madhyama, a middle king who is stronger than both of them, and
4. Udasina (kingdom lying outside or neutral and more powerful than that of Vijigishu, Ari, and Madhyama).

• Each of them has an ally and an ally's ally, making a total of 12 kings and 60 different combinations known as material constituents.
• Together, these make up the 72 components that make up the Raja Mandala.
• This plan is predicated on the idea that two neighboring governments that share borders are at war with one another and that an adversary of an at war neighbor is a natural ally. 

Hence, the correct option is 3.