Answer:
The correct answer is letter "D": Cindy can claim Mark as a dependent and she can file as head of household.
Step-by-step explanation:
Dependents are taxpayers who as such have the right to demand deductions on a tax return. They can be "qualified child" or "qualified relative." The 2017 effective credit is $4,050. Therefore, Mark can be considered as dependent on Cindy because they lived with nobody else in the same household during the same year, even if he is not employed and he is not disabled.
Being head of the household for taxing purposes means paying more than half of the household expenses, not being married for the past year, and having a qualified dependent. Therefore, as Cindy provided all of her household's assistance, has not recently married, and has Mark as her dependent, she can be called household head.