Option 1 -> Afghanistan: India shares approximately 106 km border with Afghanistan through the Wakhan Corridor in the Gilgit-Baltistan region (PoK).
Option 2 -> Nepal: India shares approximately 1,751 km border with Nepal, which is one of India's longest land borders.
Option 3 -> Bhutan: India shares approximately 699 km border with Bhutan across four Indian states.
Option 4 -> Myanmar: India shares approximately 1,643 km border with Myanmar across four northeastern states.
Hence, Afghanistan -> India's border with Afghanistan (approximately 106 km) is the shortest among all its neighboring countries. This border exists in the disputed territory of Jammu and Kashmir, specifically through the Wakhan Corridor region controlled by Pakistan (PoK). Due to the geopolitical situation, this border is not directly controlled or managed by India at present. -> correct