Which of the following taxpayers does not have to file a tax return for 2009?
A single taxpayer who is under age 65, with income of $ 9,400
Married taxpayers (ages 45 and 50 years), filing jointly, with income of $ 18,900
A student, age 22, with unearned income of $ 1,200 who is claimed as a dependent by her parents
A qualifying widow (age 67) with a dependent child and income of $ 14,500
All of the above taxpayers must file a return