题目下列分式中，最简分式是()(\quad)()A.x2−1x2+1\dfrac{x^{2}-1}{x^{2}+1}x2+1x2−1B.x+1x2−1\dfrac{x+1}{x^{2}-1}x2−1x+1C.x2−2xy+y2x2−xy\dfrac{x^{2}-2xy+y^{2}}{x^{2}-xy}x2−xyx2−2xy+y2D.x2−162x+8\dfrac{x^{2}-16}{2x+8}2x+8x2−16知识点：最简分式章节：第18章 分式 / 18.1 分式及其基本性质 / 18.1.2 分式的基本性质
