Zscaler Data Protection is primarily adopted to prevent sensitive data from leaving through internet and cloud application channels. The service combines inline DLP, SaaS Security API, endpoint controls, and data discovery to protect data in motion, at rest, and in use. Option C (Prevent loss to Internet and Cloud Apps) is correct because preventing loss to internet and cloud apps is a core data-protection use case.

Why the other options are incorrect:

A. Reduce your Internet Attack Surface: Attack surface is the set of exposed services, addresses, applications, and entry points an attacker can discover.

B. Prevent download of Malicious Files: Blocking malicious downloads is threat protection through malware, ATP, sandbox, or file controls rather than DLP for sensitive data loss.

D. Securely connect users to Private Applications: Secure private-app connectivity is the ZPA use case, not Zscaler Data Protection.