the book description at all of those links does contain a spoiler for one of the quizzes in the book, so be careful. here's a spoiler-free description of the book, taken from the introduction:
Each of the thirty-six quizzes in this book consists of sixteen questions, arranged into four groups (A, B, C, and D) of four questions each. The first challenge is straightforward: read the questions and then try to think of as many answers as you can.
But that's just the beginning. Within each group, there is some connection between the four answers. If you can figure out the answers to all four, or sometimes just two or three, of the questions in the group, the next step is to figure out the connection that ties the group together. It's a little bit like figuring out the theme of a crossword.
If you figure out the connections for all four groups, there's one final step: there is a connection between the four connections in each game!