All of the following are problems with using purchase data to understand product form and category competition EXCEPT that:
A. Brand switches occur across complements as well as substitutes.
B. They represent what consumers actually do, not what they might do
C. The data collected are often at the household level
D. Brand switch for variety may be mistaking inferred as switch due to substitutability
E. Observed brand switching could be due to different household members preferences
Answer: B. They represent what consumers actually do, not what they might do.