Answer choice (B) is correct because this weakness is stated in lines 12 to 16: "the rules provide vague guidance at best, making disqualification dependent on whether the judge's impartiality 'might reasonably be questioned,' without giving any idea of whose perspective to take..."
In other words, the rules fail to specify whose perspective should be considered when determining whether a judge may be biased.
Answer choice (A) is incorrect for a couple reasons:
(1) The passage never claims that the rules themselves interfere with judges' reasoning about cases.
(2) The author suggests that we should require judges to make their reasoning transparent and presents a potential objection to this suggestion i.e. that judges may obscure their own reasoning. Under the current rules regarding recusal and disqualification, judges are not required to make their reasoning transparent, meaning that this potential source of interference is not at issue under the current system.
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