Q. Which of the following countries are known for having the two longest borders in the world?
Answer:
United States and Canada
Notes: The United States and Canada share the longest international border in the world, measuring approximately 8,891 kilometers (5,525 miles). Russia and China have the second-longest border, at about 4,300 kilometers (2,670 miles). Brazil and Argentina, while having borders, do not surpass these lengths. India and Bangladesh have a lengthy border as well, but it is shorter than the others mentioned.