Don and Deidra are married but they have not lived together for the last three years. Don and Deidra are not legally separated and she will not agree to file a joint return. for the past two years Don's father Wyatt has lived with him. Wyatts only income is a pension of 2500 and social security of 3950. Don pays all the costs of keeping up the home and can claim Wyatt as a dependent. Don has no other dependents and no one else lived in the home. What is Don's filing status?

a) single

b) head of household

c) married filing separately

d) married filing jointly