TOEFL Listening: ETS-TOEFL听力机经 - PQYY3U1KBPQ24F84P$

Why does the professor mention refrigerators? A. To explain how the availability of electrical power led to the consumer-goods industry. B. To emphasize that they were the most important electrically power products in the 1920s. C. To indicate that access to electrical power was limited in the 1920s. D. To identity a consumer goods that was frequently advertised on the radio.