Concept:The 141° W longitude is the boundary line between Canada and Alaska.Explanation:This boundary was set by the Anglo-Russian Convention of 1825. Britain and Russia agreed that the 141° W line would separate Russian America (Alaska) from British Canada. When the U.S. bought Alaska in 1867, the border stayed the same. Later agreements between the U.S. and Canada confirmed this line. So, the longitude that separates Canada and Alaska is 141° W.Answer:Option D: 141° W