Atypical index

lists topics or names in a book alphabetically
lists page numbers for the locations of topics
usually appears at the end of a book
all the above
none of the above

All the above options are correct. Indexes may list topics or names in a book alphabetically as well as page numbers for the locations of topics. And indexes usually appears at the end of the book even thought it can appear at the beginning.

The Index words should be relevant and of interest to the reader of the book, so they can easily guide him to what he is looking for in it.

The index terms can be names, places, events, or any other terms related to your book content. They can be single words or multi words.