An application's certificate indicates the application - A is regularly updated
B cannot be removed
C is installed
D is authentic

D. is authentic

Explanation:

Authentication can be defined as the process of verifying the identity of an individual or electronic device. Authentication work based on the principle (framework) of matching an incoming request from a user or electronic device to a set of uniquely defined credentials.

Basically, authentication ensures a user is truly who he or she claims to be, as well as confirm that an electronic device is valid through the process of verification.

Biometrics, smart cards, digital certificates, and picture passwords are various methods that can be used to perform an authentication.

Hence, an application's certificate indicates the application is authentic. These certificates are generally referred to as digital certificates.

When an end user installs a software application or program, the computer or mobile device would automatically verify the digital signature contained in the software. If the authentication process is successful, the software would be installed. Else, the installation process would be terminated.

i would say 3 because windows is the best but vista doesnt do updates anymore