An - can mean either the definite article or the question form of - is. So in this sentence which is which ? Is the question word the first - an - or the second?

"Agus an inghean duit an gearrchaile seo ?" arsa mise.

If it's the second, in that case, does - gearrchaile - not only mean that she's a young girl ie an adolescent, but that she's unmarried and of marriageable age ?

Here's what follows -

"Ó' se, 'seadh, a dhearbhráthair," ar sí sin. (That's not her but her mother answering there, of course)
"Tá deallramh gearrchaile maith uirthi, Dia á beannachadh," arsa mé féin. "Bhfuil aon talamh ag gabháilt leis an tigh seo?"

The first. (An inghean duit í? = Is she a daughter of yours?)

"And is this young girl a daughter of yours?" I said
"Oh, yes, brother" she said.
"She has a look of a good girl. May God bless her." I said. "Does any ground belong to this house?"

Go raibh maith agat