听力原文：In the United States almost everyone chews gum, and more than $140 million worth

听力原文： In the United States almost everyone chews gum, and more than $140 million worth of chewing gum is sold each year. This means that, on the average, each person in the United States spends one dollar a year for chewing gum.

Chewing gum became popular in the United States mainly because of one man, William Wrigley, who was head of the Wrigley Company for many years.

In 1870 Thomas Adams began to experiment with chewing gum. It was he who first made gum soft and pleasant enough to chew. But it was not until Wrigley entered the business in about 1890 that people everywhere began to learn about chewing gum and to use it widely.

Wrigley enjoyed doing things in a big way. In his first year he borrowed money and spent more than a million dollars on advertising. On every streetcar in the United States, for years and years, there was a large advertisement telling all about Wrigley's chewing gum. People complained that wherever they went they would see the name of Wrigley. Several times Wrigley sent free-of-charge pieces of gum to every person in the telephone book of every city and town in the United States. Finally, he began to advertise that it was good for the health to chew gum. His painstaking work in advertising finally brought him huge profits.

Who was the inventor of chewing gum？

A．Thomas Adams.

B．William Wrigley.

C．Both Adams and Wrigley.

D．Unknown.