Indicate whether ordinary agarose-gel electrophoresis (A), polyacrylamide-gel electrophoresis (P), or pulsed-field gel electrophoresis (F) is used to better separate each of the following DNA molecules. Your answer would be a three-letter string composed of letters A, P, and F only, e.g. APF.
( ) Small DNA oligonucleotides such as hybridization probes and PCR primers
( ) Plasmid DNA
( ) Bacterial chromosomes