/usr/lib/libmono-2.0.so is in libmono-2.0-dev 2.10.8.1-1ubuntu2.3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libmono-2.0.so.1.0.0
/usr/lib/libmono-2.0.so.1.0.0