RainCo, a U.S. corporation, owns a number of patents related to designing umbrellas. RainCo licenses these patents to unrelated parties. TexCo, a domestic corporation, paid RainCo $100,000 in royalties related to these licenses. TexCo uses the patent information in its manufacturing process in its Canadian plant. IrishCo, an Irish corporation, paid RainCo $25,000 in royalties related to the licenses. IrishCo uses the patent information in its manufacturing process in its Michigan manufacturing plant. How much U.S.-source royalty income did RainCo earn from these licenses? 

A. $0.

B.$25,000.

C. $100,000.

D. $125,000.