Final answer:
The method is Dynamic analysis, also known as Sandbox analysis, which involves executing unknown submissions in a controlled virtual environment to monitor their behaviors and determine real-world effects.
Step-by-step explanation:
The type of Wildfire analysis method that supports a custom-built, evasion-resistant virtual environment where previously unknown submissions are executed within a virtualized test environment to determine real-world effects and behavior is known as Dynamic analysis. This method actively executes the sample in a controlled environment to monitor its behaviors, such as changes made to files, network activity, and registry modifications. This process is commonly referred to as sandbox analysis, as it provides a secure environment, or 'sandbox', where the potentially dangerous code can be run without affecting the host system. It differs from static analysis, which examines the code without executing it, and from behavioral analysis, which might be a broader term that encompasses the results from both static and dynamic analysis methods but doesn't specifically refer to a sandboxed environment.