Which deed would a seller use if he warrants that he owns the property and has had no title problems during his period of ownership but makes no warranty against defects existing before the time of his ownership?

The correct choice is a Special Warranty Deed. This type of deed is utilized when the seller guarantees that they have not encountered any title issues during their ownership of the property. However, it does not extend that warranty to any claims or defects that may have existed prior to the seller's period of ownership.

In a Special Warranty Deed, the seller is essentially saying, "I am only responsible for any issues that arose during the time I owned this property." This makes it less comprehensive than a General Warranty Deed, which provides broader guarantees about the title's history and protects the buyer against problems that existed before the seller’s ownership.

The Warranty Deed and General Warranty Deed typically offer more extensive guarantees, promising freedom from any claims regarding the property's title from its origins. In contrast, a Quitclaim Deed transfers any interest or rights the grantor has in the property without any warranties, which doesn’t suit the conditions outlined in the question.

Therefore, the Special Warranty Deed is appropriate when the seller wants to provide a level of assurance about their ownership while limiting liability for prior title issues.