The statement in the given question that presents a condition of the Hardy-Weinberg principle is that random mating occurs. The correct option among all the options given in the question is option "C". There are definitely certain conditions under which the Hardy- Weinberg principle occurs and they are when there is no gene flow, no mutations happen, no generic drift occurs and random mating occurs. This principle also states a very important aspect and it is that genotype and allele frequencies will always remain constant from one generation to another if there is absence of other evolutionary inflrnce.