Q1: Radio Button "In what condition did you get your car?"
Options:
new::I bought it new
second-hand::I bought it second-hand

Q2: text (long or short)
Why did you buy your car new?
Branching:
Parent element: Radio button 1 "In what condition did you get your car?"
Parent content: new (as prompted by the online help that says to use label)
Upon saving:
Notice: Undefined index: in moodle\mod\survey\field\multiselect\plugin.class.php on line 233

Actually, the Parent content option is expected to be the actual text, not the "label".