Crystal is 42 years old. Her husband died during the tax year, and she has not remarried. Her deceased husband had no income. She has two minor children living with her. Crystal paid all of the costs for keeping up her home for the tax year, and she has paid for all of the support of her husband and their children. Which filing status that Crystal qualifies for has the lowest tax rate?

A. Married filing jointly B. Qualifying widow with dependent child C. Married filing separately D. Head of household