eudc-multiple-match-handling-method

eudc-multiple-match-handling-method is a variable defined in `eudc-vars.el'.
Its value is

select

Documentation:
What to do when multiple entries match an inline expansion query.
Possible values are:
`first' (equivalent to nil) which means keep the first match only,
`select' pop-up a selection buffer,
`all' expand to all matches,
`abort' the operation is aborted, an error is signaled.

You can customize this variable.