please show all work/explanations.

21. A simple trust has a distributable net income (DNI) of $45,000 and net accounting income of $50,000, all from taxable sources. The trust has a sole beneficiary, Nick. The trust reports on a calendar tax year and distributes the $50,000 of 2019's net accounting income to Nick on January 20, 2020. No other distributions are made in the current year. Nick's taxable income from the trust this year is A) $0. B) $45,000. C) $50,000. D) none of these