By far, the largest security exposure in application system development relates to

A.
Maintenance and debugging hooks.

B.
Deliberate compromise.

C.
Change control.

D.
Errors and lack of training

Explanation:
Maintenance hook – instructions within a program’s code that enable the developer or maintainer to
enter the program without having to go through the usual access control and authentication
processes. They should be removed from the code before being released for production; otherwise,
they can cause serious security risks. They are also referred to as trapdoors. – Shon Harris All-in-one
CISSP Certification Guide pg 933