Steps to reproduce:
1. Log in as admin.
2. Go to Content/Forms and start adding a new form.
3. Drag and drop on the form such a Select field.
Result: You see "Choose an Option"
4. Give the field a name and save the form.
5. Place a Form portlet on a page and select the form created above.
Result: You see the text "Choose an Option"
6. Change the portal language to German
Result: "Choose an Option" text remains in English.
Expected: This text should be in German.