/usr/lib/libmono-2.0.so.1 is in libmono-2.0-1 3.2.8+dfsg-4ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libmonoboehm-2.0.so.1
/usr/lib/libmonoboehm-2.0.so.1