Biết ( int limits_{}^{} {f left( x right)dx} = {x^2} + C. ) Tính ( int limits_{}^{} {f left( {2x} right)dx} . )

A.\(\int\limits_{}^{} {f\left( {2x} \right)dx} = \frac{1}{2}{x^2} + C.\)

B. \(\int\limits_{}^{} {f\left( {2x} \right)dx} = \frac{1}{4}{x^2} + C\)

C.\(\int\limits_{}^{} {f\left( {2x} \right)dx} = 2{x^2} + C\)

D.\(\int\limits_{}^{} {f\left( {2x} \right)dx} = 4{x^2} + C\)