Final answer:
AppLocker is the solution that will block untrusted application sources from running.
Step-by-step explanation:
AppLocker is the solution that will block untrusted application sources from running. AppLocker is a Windows feature that allows administrators to specify which applications are allowed to run on a computer or a group of computers. By creating a set of rules, AppLocker can prevent untrusted applications from executing.
While anti-malware software can help detect and remove malicious software, it does not specifically block untrusted application sources from running. A firewall is a network security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It is not designed to handle application source blocking. A VPN (Virtual Private Network) is used to create a secure connection over the internet, but it does not deal with blocking untrusted applications.