Fields to retrieve - read data

Hi,
i have a mysql table (named Comuni) with all the italian city. I have to populate a dropdown control (named Citt) with the names of city.
Using a read data (read_data15) control, which values goes in 'fields to retrieve' field?
Please see also the screenshot attached.

structure of table Comuni:

CREATE TABLE IF NOT EXISTS `comuni` (
`Istat` int(6) default NULL,
`Comune` varchar(35) default NULL, ----> name of city
`Provincia` varchar(2) default NULL,
`Regione` varchar(3) default NULL,
`Prefisso` int(6) default NULL,
`CAP` varchar(5) default NULL,
`CodFisco` varchar(4) default NULL,
`Abitanti` int(7) default NULL,
`Link` varchar(38) default NULL
)

Thank you so much! it was simple, now it works!

Dear all,
using {var:read_data15} returns a structure like {"Roma":"Roma"}.
How to get just the value "Roma" to be used sending an email?
I'm trying to get value using {var:read_data15[0]} or {var:read_data15['0']} or {var:read_data15['Comune']} but I always obtain an empty string
Please, could you help me?

Hi touretteroma,
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I think that you are trying to do something completely different - this thread is about reading data to populate a drop-down. You should be able to get the selected value of the drop-down using {data:input_name}
​
Bob

Dear Bob,
I created topic https://www.chronoengine.com/forums/posts/t105472 to better explain my case.
Regards
Tourette Roma