The correct answer is Myanmar. Bangladesh has exactly two land-border neighbours: India, which surrounds it on the west, north and east, and Myanmar, with which it shares a comparatively short border in the southeastern Chittagong Hill Tracts and Cox's Bazar region. This Myanmar border has gained considerable current-affairs significance in recent years because of the large-scale movement of Rohingya refugees from Myanmar's Rakhine State into Bangladesh, particularly since the major exodus of 2017, making the frontier a frequent subject in both geography and international-affairs sections of competitive exams. Bangladesh's border with India, by contrast, is the longest of the two by far and is one of the most heavily fenced international borders in the world. Bhutan is incorrect because Bangladesh does not share any direct border with Bhutan; substantial Indian territory, including parts of West Bengal, lies between them. Nepal is incorrect for the same reason: despite being a fellow SAARC member and geographically not far away, Nepal is separated from Bangladesh by the narrow Indian Siliguri Corridor and the state of West Bengal, so the two countries are not physically contiguous. China is incorrect because although China lies north of the wider region and borders both Nepal and Bhutan, it is far removed from Bangladesh and shares no boundary with it at all. A common exam confusion is assuming that because Bangladesh is almost entirely enclosed by India, it must have no second land neighbour, overlooking the Myanmar frontier in the far southeast. The revision takeaway is to remember Bangladesh's border profile as exactly two countries, India (long, encircling) and Myanmar (short, southeastern), while Bhutan, Nepal and China remain non-contiguous with it despite regional proximity.
