In part (a) of the figure, a current pulse increases to a peak and then decreases to zero in the direction shown in the stimulating coil. What will be the direction of the induced current (dashed line) in the brain tissue?

(a) 1;

(b) 2;

(c) 1 while the current increases in the stimulating coil, 2 while the current decreases;

(d) 2 while the current increases in the stimulating coil, 1 while the current decreases.