Sentence Correction (SC) | Even though it was not illegal for the bank to share its customers'

Here is my analysis,

the sentence we are trying to correct describes about "the state's attorney general accusation"

If you closely observe the meaning,

The accusation was that the bank engaged in deceptive business.
in options D,E it says the bank engaged in deceptive business because of its failure in honoring/to honor promise.
It didn't engage in deceptive business because it failed.
It engaged in deceptive business and therefore failed to keep promise.
I eliminated C also with
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