The presence of the .rar extension on this specific version typically indicates a compressed archive often found on third-party sharing sites or forums rather than official Adobe distribution channels. This raises two critical points of analysis:

Using a version from 2021 means missing years of critical security updates. Modern threats often exploit unpatched versions of Acrobat to execute code via specially crafted PDF files. Conclusion

The "DC" branding highlights Adobe’s move from perpetual licenses to the Creative Cloud subscription model, ensuring users always have the latest security patches and features.

Encrypting user data immediately upon execution of the setup file.

This era of Acrobat focused heavily on making documents readable for all, including automated tagging for screen readers and meeting global standards like PDF/UA.