:3. Diagram ? on page ? represents a scatter diagram each point
of which represents the IQ scores of a married couple. The x-
coordinate of a point represents the husband's IQ, while the y-
coordinate represents the wife's IQ. The solid line is the
regression line for the wife's IQ from the husband's IQ. The
regression line for the husband's IQ from the wife's is given by <p>

a.  the solid line <p>

b.  the dashed line <p>

c.  the dotted line