Liang, an NRA, Is Sent to the United States by Fuller

Multiple Choice

Liang, an NRA, is sent to the United States by Fuller Corporation, her foreign employer. She spends 50 days in the United States and earns $20,000 for a two-month period. This amount is attributable to 40 U.S. working days and 10 non-U.S. working days. Her employer does not have a U.S. trade or business and Liang spends no other time in the U.S. for the tax year. Liang's U.S.-source taxable income is:

A) $20,000.
B) $16,000.
C) $3,000.
D) $0.