What can initiate the triggering phase of a virus?

The triggering phase of a virus is initiated when a specific condition within the system is met. This condition can often be a user action, such as opening a particular file or application, or it can be set to a specific date. For instance, some viruses are designed to activate on a predefined date, like an event anniversary, or in response to certain user interactions. This is a critical aspect of how many viruses operate, enabling them to remain dormant until they can maximize their impact.

Other options do not universally support triggering mechanisms for viruses. Software updates may alter system components or software but typically do not specifically trigger virus activation. Scans by antivirus software are designed to detect malicious activity rather than trigger it. Changes in system configuration might affect virus behavior but are not specifically intended to initiate the virus. Therefore, linking the activation specifically to a user action or predetermined date correctly encapsulates how many viruses engage their triggering phase.