Let P(x)=x4−4x3+6x2−4x+k.P(x)=x^4-4x^3+6x^2-4x+k.P(x)=x4−4x3+6x2−4x+k. Exactly one real value of xxx satisfies P(x)=0P(x)=0P(x)=0. What is the value of kkk? A000B111C222D444E888