The correct answer to this open question is the following.
Although there are no options attached, we can say the following.
The role that the whaling industry played in American expansion in the Pacific in the first half of the 19th century was that it represented a profitable business for people and contributed to the development of the industry in the United States because whale oil was an important component for illuminating houses, streets, business, and cities in that time. Furthermore, in that time, the sperm of the whales was used as a form of lubricant for the machines in the fabrics of the industrial United States.