It's funny what other things you remark if you try to take a course as a student! One starts to understand more why people ofte find Moodle's navigation so complex. F.i. after I submit a Choice, nothing seems to happen. All you is a button "Remove my choice". What you would like to see is something like "Your choice has been recorded. You can go back to the Course." Or simpler, just a button Back to course page.
When you save your choice you will get a message in green box above choice question that "your choice has been saved" as shown in screenshot below.