Sentence 4 establishes that while human biases have localized consequences, AI, represented by Al, amplifies these impacts globally, setting the stage for subsequent points.
Sentences 1 and 2 address AI bias. Sentence 1 details how online algorithms accessible to many magnify biased decision effects on larger populations. Sentence 2 defines "algorithmic bias" as originating from training data, not algorithms, explaining that algorithms replicate data patterns. Thus, Sentence 2 logically supports Sentence 1.
Sentence 3 observes that AI biases, despite their reach, are easier to fix than human biases because algorithmic flaws are more readily identified and corrected than ingrained human behaviors. This follows logically from Sentence 2's explanation.
Consequently, the correct order is (A): 4123