Given, $$x^4 + x^{-4} = 47$$
$$=$$> $$x^4+\frac{1}{x^4}+2=47+2$$
$$=$$> $$\left(x^2+\frac{1}{x^2}\right)^2=49$$
$$=$$> $$x^2+\frac{1}{x^2}=7$$
$$=$$> $$x^2+\frac{1}{x^2}+2=7+2$$
$$=$$> $$\left(x+\frac{1}{x}\right)^2=9$$
$$=$$> $$x+\frac{1}{x}=3$$
$$=$$> $$x^2-3x+1=0$$
$$=$$> $$x^2-3x=-1$$
$$\therefore\ \left(2x-3\right)^2=4x^2+9-12x=4\left(x^2-3x\right)+9=4\left(-1\right)+9=5$$
Hence, the correct answer is Option A
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