Which is the polynomial function of lowest degree with rational real coefficients, a leading coefficient of 2 and roots 7√ and 3? A. f(x)=x3−3x2+7x−21f of x is equal to x cubed minus 3 x squared plus 7 x minus 21

B. f(x)=2x3−6x2+14x−42f of x is equal to 2 x cubed minus 6 x squared plus 14 x minus 42

C. f(x)=x2+4x−21f of x is equal to x squared plus 4 x minus 21

D. f(x)=2x2+8x−42