A certificate is a digital document that verifies the identity and authenticity of a website or a server. Certificates are issued by trusted authorities, such as Certificate Authorities (CAs), and are used to establish secure connections between clients and servers, such as when browsing the web or accessing online services. Certificates can also be used to encrypt and decrypt data, sign and verify documents, and authenticate users and devices.

To access commercial web pages through a corporate proxy server, users are required to install a certificate that is trusted by the proxy server. This certificate can be obtained from the proxy server administrator or from the website itself. To verify that the needed certificate is installed on a Windows computer, users can use the Internet Options applet in the Control Panel. The Internet Options applet allows users to configure various settings related to internet browsing, such as security, privacy, connections, and content. To view and manage certificates, users can follow these steps:

Open the Control Panel and click on Internet Options.

In the Internet Options window, click on the Content tab.

In the Content tab, click on the Certificates button.

In the Certificates window, users can see the list of certificates that are installed on their computer, categorized by purpose, such as personal, trusted root, intermediate, or untrusted. Users can also import, export, remove, or view the details of each certificate.

The correct answer is D. Internet Options, as it is the applet that enables users to verify the needed certificate is installed.

References:

CompTIA IT Fundamentals+ (ITF+) Certification Exam Objectives, page 17, section 4.2

CompTIA IT Fundamentals+ (ITF+) Study Guide, page 217, section 8.3

CompTIA IT Fundamentals+ (ITF+) All-in-One Exam Guide, Second Edition, page 315, chapter 10