From the 1970s through the 1990s, the relative price of a college education has increased greatly. During the same time period, college enrollment has also increased. This evidence suggests that during this time period:_____. A) the demand curve for a college education has shifted leftward. B) the supply curve for a college education has shifted rightward. C) the demand curve for a college education has shifted rightward. D) the supply curve for a college education has shifted leftward.