Assume that the demand curve for a certain good is a vertical line. This vertical demand curve illustrates the idea that:
a.consumers are unwilling to pay more than a certain price for the good.
b.the good is a complement to another good.
c.consumers are unwilling to pay less than a certain price for the good.
d.there are many substitutes for this good.
e.people will not change the quantity of the good when the price of the good is changed.