i just want to transfer a 100 files
To transfer 100 files that are not a sequence set you can use this:
rsync -P `ls source-dir/ -U | head -100` destination-dir/
There's no option of rsync (that I can find) that just transfers 100 and stops
Instead you need to find a way to select 100 files to pass to rsync as a list
If the source folder is a remote one, you may have to mount it (auto-fs maybe)
rsync -P `ls /mnt/source-dir/ -U | head -100` destination-dir/