________ rearranges objects to use disk space more efficiently, thus releasing the now unused space to be used again

To make it easier to read, you could use a ________ line to separate two blocks of text

A) separator B) paragraph C) vertical D) horizontal

From the following list, identify a valid Class B IP address

A) 127.16.01 B) 129.112.54.6 C) 192.1.1.4 D) 101.32.255.255