According to the passage, what does the author thi

单项选择题

A scientist who does research in economic psychology and who wants to predict way in which consumers will spend their money must study consumer behaviors. He must obtain data both on the resources of consumers and on the motives, that tend to encourage or discourage money spending.
If an economist were asked which one of the three groups borrow most— people with rising incomes, stable incomes, or declining incomes— he would probably answer: those with declining incomes. Actually, in the years 1947 to 1950, the answer was: people with rising incomes. People with declining incomes were next and people with stable incomes borrowed the least. This shows us that traditional assumption is that if people who have money expect prices to go up, they will hasten to buy. If they expect prices to go down, they will postpone buying. But research surveys have shown that this is not always true. The expectations of income increases may not stimulate buying. One typical attitude was expressed by the wife of a mechanic in an interview at a time of rising prices. "In a few months," she said, "we"ll have to pay more for meat and milk, we"ll have less to spend on other things." Furthermore, the rise in prices that has already taken place may be resented and buyer"s resistance may be evoked. This is shown by the following typical comment: "I just don"t pay these prices, they are too high."
Traditional assumptions should be investigated carefully, and factors of time and place should be considered. The investigations mentioned above were carried out in America.
Investigations conducted at the same time in Great Britain, however, yielded results that were more in agreement with traditional assumptions about saying and spending patterns. The condition most conductive to spending appears to be price stability. If prices here been stable and people have become accustomed, to consider them "right" and expect them to remain stable, they are likely to buy. Thus, it appears that the common business policy of maintaining stable prices with occasional sales or discounts is based on a correct understanding of consumer psychology.

According to the passage, what does the author think of the traditional assumptions about consumer behavior

A．The assumptions are not always true.
B．They are in reliable.
C．They are in consistent with the findings in investigation.
D．The assumptions are not at all wrong.