Answer:
The author used what is called "amplification through simplification" technique.
Step-by-step explanation:
In both panels of Persepolis 2, the author is using the well-known technique "amplification through simplification". The aim of this technique is to reveal the essential meaning by "simplifying" the image - deleting any unnecessary baggage, which allows an amplification of its message. That's the reason why the author used black and white as the primary colors in the images, making us focus more on the words and characters' changes, rather than the background of them.