You are an expert Visual Pattern Analyst. Your task is to solve a Bongard Problem puzzle in a classification setting. (one of them has one pair of images from respective sides switched so the rules of the task are broken)

You are presented with two possible sets of images (A and B). 
### Instructions:
Identify which set (A or B) represents a valid Bongard Problem classification, where all images on the **Left** side share a consistent visual invariant absent from the **Right** and which set contains a single pair of interchanged images that violates this rule.

* Only use information provided in the images. Do not infer any hidden rules, patterns, or details not explicitly stated. Answer in less than 500 words.*
