The misleading title that brought this dialogue to my attention is where there is only one selected item to move to the trash. In this case the question wording is correct but the message box title says "Delete Permanently?". This is the code for "case Trash" and "if (prettyList.count() == 1)" in KIO::JobUiDelegate::askDeleteConfirmation().
This should be corrected to say "Move to Trash" as in the other conditional below.
There are some other anomalies which are also corrected in this diff:
a) The "Delete Permanently" message box title has a question mark, but "Move to Trash" does not. I can't find a HIG rule for which of those is correct, but for consistency and in accordance with "Do not use the title to explain what to do in the dialog – that’s the purpose of the main instruction" the question marks are removed.
b) Capitalisation of "Trash" made consistent in the question for trash of multiple items.