已知函数 f(x),g(x)f\left( x\right) ,g\left( x\right)f(x),g(x) 的定义域均为 R\mathbf{R}R ,且 f(x)+g(2−x)=5,g(x)−f(x−4)=7f\left( x\right) + g\left( {2 - x}\right) = 5,g\left( x\right) - f\left( {x - 4}\right) = 7f(x)+g(2−x)=5,g(x)−f(x−4)=7 . 若 y=g(x)y = g\left( x\right)y=g(x) 的图像关于直线 x=2x = 2x=2 对称, g(2)=4g\left( 2\right) = 4g(2)=4 ,则 ∑k=122f(k)=\mathop{\sum }\limits_{{k = 1}}^{{22}}f\left( k\right) =k=1∑22f(k)= ( )A. -21 B. -22 C. -23 D. -24