Purpose: to sell a product.

Audience: People watching TV, teenagers or young adults

What makes it a powerful image: 
The use of color red makes people feel hungry; the image is appetizing.
A famous person (Katy Perry) is involved. The image presents chips as healthy products (not causing you to put on weight.) 
We can see the “contrast” and “focus” as the main visual strategies in this image. It uses strong visual contrasts, lights and darks; red, black and white. The celebrity is the focus of the image. 

I chose this image because many ads use similar strategies and they know how to manipulate their audience with the help of images/visuals.