Final answer:
The medium of Yves Klein's Anthropometries de l'epoque bleue is performance art involving the use of human bodies covered in blue paint.
Step-by-step explanation:
The medium of Yves Klein's Anthropometries de l'epoque bleue is performance art.
In these works, Klein directed models to cover themselves in blue paint and imprint their bodies onto canvases, creating abstract compositions.
This was a form of art that involved the live presence of the artist and the engagement of the human body in the creation of the artwork.