One Commonly Used STR Is Called "TH01," Found on Chromosome

One commonly used STR is called "TH01," found on chromosome 11.Let's say we have STR information on TH01 from DNA profiles of both of Marcus's parents.Which is the most likely description of TH01 differences between Marcus's parents?

A) Mom has three copies of TH01 and Dad has five copies.
B) Mom has TH01 and Dad does not.
C) Dad has TH01 and Mom does not.
D) Mom's TH01 has a different sequence than Dad's TH01.
E) Any of these are likely possibilities.