Answer:
Head of household; 2 dependents
Explanation:
For filing under 'head of household' status, a taxpayer must fulfill following conditions:
1. Taxpayer must pay more than 50% of household expenses.
2. In the tax year, the taxpayer must be unmarried.
3. The taxpayer must have either a qualifying child or a dependent.
John fulfills all the above conditions.
John is married and take care of his parents' expenses. His parents are dependent on him even though they do not stay with him for the entire year as he has contributed more than half of their living expenses.
Therefore, John can file as 'head of household'.
He can claim 2 dependents on his 2018 tax return, his father and mother.
