A、Horse riders. B、Teenage girls. C、Canadian parents. D、International travelers. C选项表明，本题考查人物身份。短文通篇在介绍Shadow Ridge Summer Camps，

Camp memories last forever! We make sure they are unforgettable!
Shadow Ridge Summer Camps offer so many exciting things for campers to do. Unlike the other camp programs that include horses as a small part of their program, at Shadow Ridge horses ARE the program! We are 100% horse from stable management, nature walks, and track rides to bedroom furnishings.
    Horses help us achieve many of our aims. Girls can learn to develop responsibility, self-confidence and personal connections in their lives while having fun. Using horses as a wonderful tool for education, our camps offer an interesting place for growth and learning.
    Imagine each girl having her very own horse to spend time with and a best friend to love and take care of. Each camper is responsible for a horse for the week. Our riding program provides a lot of riding and lesson time. Campers will learn how to take care of the horse and the tack, as well as how to ride. Days are filled with horse-related activities to strengthen the connection between each girl and horse, as the girls learn to work safely around the horses.
    At Shadow Ridge we try to create a loving, caring family atmosphere for our campers. We have "The Bunkhouse"(4 girls), the "Wranglers Roost"(4 girls), and "The Hideout"(2 girls)in our comfortable 177-year-old farm house. All meals are home-cooked, offering delicious and healthy food for the hungry rider.
    Our excellent activities create personalized memories of your child’s vacation. Each child will receive a camp T-shirt and a photo album(usually 300-500 pictures)of their stay at camp.
    Our camps are offered during June, July and August, 2007, for small groups of girls aged 13-16 years, not only from Canada but also other parts of the world.
    We will send you full program descriptions at your request.
Questions 16 to 19 are based on the passage you have just heard.
16. What is the main topic of this passage?
17. What do we know about the camp programs at Shadow Ridge?
18. What is the main aim of programs at Shadow Ridge?
19. Who is the passage mainly written for?