Answer:
Links to sites where readers can buy her favorites
Step-by-step explanation:
The feature that Rhetta should include to help people get copies of her suggestions are links to sites where they can buy them. This way, her readers can visit the websites these links lead to, check out the prices, and order the novels she suggested.
The rest of the options would be useless to readers who want to purchase these books. Audio of Rhetta reading passages would help them see if they like the book, links to other blogs about reading and mysteries would help them discover more books, and a chart that includes how many copies were sold of each book would just show popular they are.
This is why the first option is the correct one.