Why is there more than one single locus probe used in actual paternity dna test?

There is the application of more than one single locus probe in the actual paternity test as one receives half of the genetic substances from the mother and half from the father. There is more than one probe that is needed to examine both parent's identity.  

Or it can be said that the locus probes are utilized to determine various intervening repetitive sequences of DNA that are situated in different chromosomes and leads to the production of 30 and 20 bands, thus, one can avoid the chances of a similar pattern due to multi-band patterns.  

answer; i believe the correct answer is (a)0

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: