Amaury, a citizen of France with no trade or business activities in the United States, sells at a gain 200 shares of Gage, Inc., a U.S. company. The sale takes place through Amaury's broker in Paris. How is this gain treated for U.S. tax purposes? a. It is U.S.-source income subject to U.S. taxation. b. It is foreign-source income subject to U.S. taxation. c. It is U.S.-source income exempt under a treaty. d. It is foreign-source income not subject to U.S. taxation. e. It is U.S.-source income exempt from U.S. taxation