Please help with these 2 multiple choice q's?

I believe the first one is c). DNA uses polymerase 1 and 3 for synthesis in the cells, and in PCR uses the Taq polymerase for replication because this polymerase can stand the high temperatures needed for PCR. The second one is b). The ladder is only a reference to see where the separated bands are. The electricity used in the gel box is what separates the DNA, and the dye mixed with the DNA is what makes the bands show up.