The two karyotypes belong to a donkey (Q) and a horse (R).
Breeding these two individuals resulted in the production of a sterile mule (S).
Why would S be sterile?
The sex of the mule (S) will be undetermined at birth due to the unnatural combination of chromosomes
Different combinations of alleles formed as a result of crossbreeding Q and R which leads to disadvantageous characteristics in S
There are different numbers of chromosomes in the gametes of Q and R so S would not live long enough to breed
The process of meiosis will not be possible in S as homologous pairs cannot form