What Does the "Substitution Bias" in the Consumer Price Index

What does the "substitution bias" in the consumer price index refer to?

A) substitution of new goods for old goods in the purchases of consumers
B) substitution of quality for quantity in consumer purchases over time
C) the fact that consumers substitute toward goods that have become relatively less expensive
D) substitution of new prices for old prices in the basket of goods from one year to the next