Concept:
This matching exercise covers a broad timeline of Indian foreign policy and significant political changes in the neighboring Himalayan region.
Step 1: Analyzing Foreign Policy Shifts.
• A. Act East Policy (2014): At the ASEAN-India Summit in November 2014, Prime Minister Narendra Modi upgraded the "Look East Policy" (of the 1990s) to the more proactive "Act East Policy." (A-II)
• B. Indus Water Treaty (1960): This water-distribution treaty between India and Pakistan, mediated by the World Bank, was signed in Karachi in September 1960. (B-I)
Step 2: Analyzing Regional Military and Constitutional Events.
• C. IPKF pullout (1989-90): The Indian Peace Keeping Force (IPKF), which had entered Sri Lanka in 1987, began its final withdrawal following a change in government in India. The process was largely completed by late 1989 and early 1990. (C-III)
• D. Nepal's New Constitution (2015): After years of transition from a monarchy to a republic, Nepal formally adopted its current secular, federal constitution in September 2015. (D-IV)
Step 3: Final Sequence.
The combination A-II, B-I, C-III, D-IV matches Option (1).