to be "considered unmarried for head of household status", which of the following statements is not correct?

Choose one answer. 

a. The taxpayer's spouse must not have lived in the house for the last six months of the tax year.

 b. The taxpayer must be able to claim an exemption for the child or the taxpayer cannot claim the exemption only because the noncustodial parent is allowed to claim the exemption for the child.

 c. The taxpayer paid more than half the cost of keeping up the home for the tax year. 

d. The taxpayer's home was the main home for his or her child, stepchild, foster child or parent for over six months of the tax year.