[Fechado] Translating third party drop down menu

Background of the issue:
I am trying to translate a third-party dropdown menu on my website (mobile version). I can't find a value or string in the admin section that says 'Select Options'. How do we translate this? Please see the attached screenshot: link oculto.

Symptoms:
I expected to see 'Select options' translated, but I can't find any options for translating this text.

Questions:
How do I translate the 'Select Options' text in a third-party dropdown menu?