Here's a nice graphic of Helvetica overlaid with Arial with the same font weight and kerning.

http://snth.net/~rlk/image/helvetica-vs-arial-2.png

In this comparison, the capital E's are identical, so perhaps MATTEL used a different weight Helvetica?

I picked the one with the longest distance between the T and the E. That was the wrong answer.

This quizz is an excellent training though. I didn't know anything at all about typography prior to taking the test (never bothered to learn the names of the fonts or their shapes), ended up scoring 17/20.