请教一道小小SC~旧prep

ruiqijjkkl

105. (30121-!-item-!-188;#058&004107)

Even though it was not illegal for the bank to share its customers' personal and financial informationwith an outside marketing company in return for a commission on sales, the state's attorney general accused the bank of engaging in deceptive business practices by failing to honor its promise to itscustomers to keep records private.
(A) by failing to honor its promise to its customers to keep
(B) by its failure of honoring its promise to its customers to keep
(C) in its failing to honor its promise to its customers of keeping
(D) because of its failure in honoring its promise to its customers in keeping
(E) because of its failure to honor its promise to its customers of keeping
答案：A
请问：A的by doing sth 不是很奇怪吗？有谁主动做一件事情是用消极的方式的？

futureflow

一点都不奇怪啊， by doing表方法