Got 68 points, which means 100-68=32 points.
And as long as you do it wrong, you will lose points. Not only can't get 5 points, but also deduct 3 points, which is 5+3=8 points less.
32/8=4 (question) is wrong by four questions.
20-4= 16 (theme)
A: Xiao Xiao did the right thing 16.