If a,b are the roots of a equation of a quadratic equation x²−3x+5=0 then the equation whose roots are (a²−3a+7) and (b²−3b+7) is-
A. x²−4x−1=0
B. x²+4x+1=0
C. x²−4x+4=0
D. x²+4x+4=0