Which condition allows a taxpayer to claim their spouse's personal exemption when filing separately?

A taxpayer can claim their spouse's personal exemption when filing separately under specific circumstances. For this to occur, the spouse must have no gross income, meaning that their income is below the threshold that would require them to file a tax return. In addition to this, the spouse cannot be a dependent of another person; this is essential because if a spouse qualifies as someone else's dependent, they cannot be claimed for a personal exemption by their partner.

Thus, when both of these conditions are met—no gross income and not being a dependent of someone else—the taxpayer is eligible to claim their spouse's personal exemption. It’s important to understand that filing jointly generally offers more tax benefits, yet under separate returns, these conditions still allow for claiming the spouse's exemption. Therefore, the correct choice encompassing these requirements is the one that includes both conditions presented.