Why does it say 4.9L V8 instead of 5.0L? And where is the V6 option?
The survey intentionally adjusted the displacement of the engine options to throw people off. Survey companies do that all the time. They want the survey taker to give an unbiased opinion (and so does the manufacturer who hired them), so they manipulate things a little bit.
Stating directly that it's a Ford Mustang or making it easy to figure out by posting the exact specifications would lead to some of the people in the random sample giving potentially biased opinions.