Answer:
A. Substitution bias and the introduction of new goods.
Step-by-step explanation:
The Consumer price index is a measure of the overall cost of goods and services (usually measured in fixed basket), purchased by a consumer in a year as compared to previous years. It gives the government and economists an idea of the cost of living of individuals in a nation. Some problems of the CPI include
1. Substitution Bias: The CPI assumes that prices of goods and services change in a fixed way as the years go by. It also does not consider the fact that sometimes some customers have preference for expensive items compare with the less expensive items. This is reflected in the OPEC case where it is automatically assumed that customers would prefer the cheaper hydrogen-powered engines to the gasoline engines.
2. Introduction of New goods: The CPI fails to recognize that new goods would enter a market because the CPI assumes a fixed basket of items and products. The introduction of new goods would affect comparisons to previous years' CPIs. The new good invented in the above case is the hydrogen-powered engine.