स्वतंत्रता के बाद से निम्नलिखित में से कौन सा भारत की विदेश नीति का एक आधारभूत स्तंभ रहा है?

During which leader's official diplomatic visit did India and China sign the 'Declaration on Principles for Relations and Comprehensive Cooperation' and agree to appoint Special Representatives (SRs) to explore a boundary settlement?

Given below are two statements, one labeled as Assertion (A) and the other as Reason (R): Assertion (A): The Gujral Doctrine sought to build a peaceful, cooperative South Asia by advocating persistent bilateral dialogue with smaller neighbors. Reason (R): The doctrine emphasized sovereign equality, non-interference in internal affairs, mutual respect for territorial integrity, and unilateral concessions without demanding strict reciprocity from smaller neighbors. In light of the above statements, choose the correct answer: