以下是计算Jf xy^2dxdy的步骤,其中D由曲线-|||-y=4x 与直线 x=1 围成。请选出正确步骤-|||-()-|||-a. iint x(y)^2dxdy=(int )_(0)^1dx(int )_(0)^4xx(y)^2dy-|||-D-|||-b. iint x(y)^2dxdy=(int )_(0)^1dx(int )_(0)^4x(y)^2dy-|||-D-|||-C. dfrac (64)(3)(int )_(0)^1(x)^4dx d. dfrac (64)(3)(int )_(0)^1xdx e. 64/15 f. dfrac (32)(3)-|||-A. a-c-f-|||-B. a-c-e-|||-C. b-c-f-|||-D. b-c-e