How many times this should be repeated
The words of the score, drawn instead of the instruction's label (e.g. "D.C."), where the label goes, as they say more than the label or say it in another language, e.g. "D.C. senza replica", "Menuetto D.C. al Fine" or "Fin". Undefined for words that only name the instruction (e.g. "Da Capo", drawn as "D.C."), and for a segno or coda sign.
Whether the MusicXML marks this segno as the target of a D.S. (): it is never taken for a D.S. itself.