Final answer:
The strongest defense against buffer overflow attacks in a custom application is parameter checking, which ensures inputs are correctly validated to prevent exploitation of the vulnerability.
Step-by-step explanation:
Aith is concerned about the use of buffer overflow attacks against a custom application developed for use in her organization. To provide the strongest defense against these attacks, option C, parameter checking, is generally the most effective security control. Parameter checking, also known as input validation, ensures that inputs to the application are checked for correctness before being processed. This is a proactive measure that can prevent attackers from exploiting buffer overflow vulnerabilities by ensuring that inputs do not exceed the expected bounds.
Other measures, such as an intrusion detection system, vulnerability scanning, endpoint security, and firewalls, are also important in an overall security strategy, but they may not be as effective in preventing buffer overflow attacks directly as they are designed to detect, manage or mitigate attacks rather than proactively prevent a specific type of vulnerability exploitation.