In the following situations, indicate whether the taxpayer qualifies as a head of household. 
a. Allen is divorced from his wife. He maintains a household for himself and his dependent mother.
b. Beth is divorced from her husband. She maintains a home for herself and supports an elderly aunt who lives in a retirement home.
c. Cindy was widowed last year. She maintains a household for herself and her dependent daughter, who lived with her during the year.
d. Dick is not divorced, but lived apart from his wife for the entire year. He maintains a household for himself and his dependent daughter. He does not receive any financial support from his wife.