Mona is self-employed working as a fortune teller. Her net income from this activity was $250 in 2022. Which of the following is true regarding her self-employment (SE) tax for the year?
Options: A) Mona is exempt from SE tax. B) Mona is only liable for SE tax if her net income exceeds $400. C) Mona's SE tax is calculated based on her gross income. D) Mona is not required to pay SE tax on her net income.