Which of These Events Would Cause the Consumer Price Index

Multiple Choice

Which of these events would cause the consumer price index to overstate the increase in the cost of living?

A) Car makers benefit from a new technology that allows them to sell higher-quality cars to consumers with no increase in price.
B) Energy prices decrease,and consumers respond by buying more gas and electricity.
C) A new good is introduced that renders cellular telephones inferior and obsolete.
D) All of the above are correct.