Simplify the rational expression. x−6/x^2−7x+6

Ax/x+1
B1/x−1
Cx−1/x+1
Dx/x

Factor out the common binomial in the expression. 12(x-5) + 7x(x-5)

A(x-5)(12+7x)
B(7x-5)(12+x)
C2(x-5)(12+x)
D(x+5)(12-7x)