Match the $x(j)$ functions with the corresponding phases $\frac{?}{{?}_x(j)}.$ Assume $>0.x(j)=\frac{4}{4+{}^2}x(j)=-\frac{4}{4+{}^2}x(j)=\frac{4j}{4+{}^3}x(j)=-\frac{4j}{4+{}^2}$ A$.\frac{?}{{?}_x(j)}=-$ B$.\frac{?}{{?}_x(j)}=-\frac{}{2}.\frac{?}{{?}_x(j)}=0$ D$.\frac{?}{{?}_x(j)}=\frac{}{2}$