The magnetic field in a region is given by \[B={{B}_{0}}\left( 1+\frac{x}{a} \right)\hat{k}\]. A square loop of edge-length d is placed with its edges along the x and y-axes. The loop is moved with a constant velocity\[v={{v}_{0}}\hat{i}.\]The emf induced in the loop is:

• A. zero      
• B. \[{{v}_{0}}{{B}_{0}}d\]
• C. \[\frac{{{v}_{0}}{{B}_{0}}{{d}^{3}}}{{{a}^{2}}}\]
• D. \[\frac{{{v}_{0}}{{B}_{0}}{{d}^{2}}}{a}\]