DNA samples have been separated out on an agarose gel, and then stained with a fluorescent DNA binding dye. The lane labeled MM shows the markers for known lengths of double-stranded DNA, and the

a) Unknown samples can be compared to the marker bands to estimate size.
b) Unknown samples can be sequenced directly from the gel.
c) Unknown samples can be visualized under UV light.
d) Unknown samples can be digested with restriction enzymes.