the letters there are answers written by people who are supposed to know how to solve such problems.
A. Along with
B. Apart from
C. According to
D. Regardless of
网友回答
(答案→)A. Along with
B. Apart from
C. According to
D. Regardless of
解析：考查介词辨析。A和…一起；B除…之外；C根据；D不管；句意：和这封信一起的是一些知道如何解决这些问题的人写的答案。根据句意说明A正确。