Afrikaners are a Southern African ethnic group descended from a very few Dutch settlers first arriving in the seventeenth and
eighteenth centuries. The small population size of the original sett.
colony probably had reduced genetic
variation as well as a non-random sample of the genes from the original Dutch population. Today, the Afrikaner population
has an unusually high frequency of the gene that causes Huntington
original Dutch colonists just
happened to carry that gene with unusually high frequency
The Afrikaners are an example of a founder effect that occurs when
population and the random decrease in genetic variation is an example
A)
genetic drift.
natural selection
c)
genetic recombination
the bottleneck effect.

The Afrikaners are an example of a founder effect that occurs when  population and the random decrease in genetic variation is an example of genetic drift.

Explanation:

When some individuals from a population move to form a new colony, this phenomenon is called founder effect as in case of Afrikaners. The small population or group of individuals forming a new colony may not exhibit the full genetic diversity of the population they were once the part.

The alleles would get expressed in different frequencies than it would have in original population.

There are chances that some alleles are lost or missing also. The new colony formed has small population so chances of genetic drift are very strong.

Genetic drift does not depend upon the benefit or harmful effect of the alleles as it occurs merely by chance sampling. The small population of Afrikaners felt the effect of genetic variation hence strong genetic drift is seen in them.