As Shown in the Figure, a Straight Wire Carries a Current

Multiple Choice

As shown in the figure, a straight wire carries a current $I$ into the page. The wire passes through the center of a toroidal coil. If the current $I$ is quickly reduced to zero, the direction of the induced current through the resistor $R$ is

A) from $b$ to $a$ .
B) from $a$ to $b$ .
C) No current is induced.