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Correct Answer: Option (A) — Canada and the United States of America
Concept & Option Breakdown
Standard Reference VerifiedThe international land border between Canada and the United States is the longest in the world, spanning approximately 8,891 kilometres (5,525 miles), which includes both the continental border and the Alaska-Canada border.
The US-Canada border is famously known as the longest undefended international land border in the world.
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