ListBox or ComboBox - which to use??

Hi all,

I want a drop down list on the first sheet of my workbook.
this should be populated with a list of vlaues in column A of another sheet (results of a query, so could increase in numbers)

I'm not sure whether to use a listbox or combobox.
(not sure of when to use one or when to use another)

I will be passing the value of this drop down into a query written in VBA.

can anybody advise.
possibily with the code that would be required to select a dynamic range in columnA of the other worksheet..

thanks in advance,

Matt