A new species develops when the two diverging species no longer recognize each other as their potential mates. In such cases, these two species evolve and grow as two completely different species. There is no genetic exchange between these two species now. When two species diverge, there are no chances of of the members of each of them mating as there DNA (Deoxyribonucleic acid) is no longer compatible.
Hence, the correct answer is 'Option A - diverging species no longer recognize one another as potential mates'.