TOEFL Listening: TPO-TOEFL阅读TPO - 5036LL526RLNT7APN$

All of the following are mentioned in paragraph 3 as resulting from the use of steam in the lumber industry EXCEPT: A. Work became centralized, and many tasks were automated. B. Lumber could be produced more efficiently and on a larger scale. C. Waste materials could be re-used as fuel to power the lumber mills. D. Lumber production could continue throughout the cold winter months.