Final answer:
The music video that features a reflection of a small Jack is 'Lose Yourself' by Eminem. In the video, a young boy, who represents a young Eminem, is shown as a reflection in a mirror.
Step-by-step explanation:
The music video that features a reflection of a small Jack is 'Lose Yourself' by Eminem. In the video, there is a scene where a young boy, who represents a young Eminem, is shown as a reflection in a mirror. This symbolizes the artist's inner struggles and how his younger self is still a part of him.