Question 319823
Factor each denominator:
{{{x^2-2x+1 = (x-1)^2}}}
{{{x^2-5x+4 = (x-4)(x-1)}}}

For the LCD we need {{{(x-4)}}} and {{{(x-1)^2}}}, so the answer is D. There's no need to take the other {{{(x-1)}}}.