/usr/share/doc/libopts25-dev/changelog.Debian.gz is in libopts25-dev 1:5.18.12-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libopts25-dev/../libopts25/changelog.Debian.gz
/usr/share/doc/libopts25-dev/../libopts25/changelog.Debian.gz