What emotion does the boy experience upon seeing the pictures?

The boy experiences joy upon seeing the pictures because they likely evoke positive memories or feelings associated with the images. This response suggests that the pictures represent something meaningful or happy to him, leading to an emotional reaction of delight. Joy is often connected to personal memories, positive associations, and experiences that elicit happiness, highlighting the value of these images in his life. The presence of joy illustrates the power of visual stimuli in triggering pleasant emotions, reinforcing the idea that our experiences and memories can significantly impact our emotional states.