Garhi is ancestral to Homo (i.e. Homo habilis
The image was missing from the question.
The correct answer is genetic drift.
As you can see, the image presents a large amount of fish being caught by a fishing net. The genetic drift is one of the four mechanisms of evolution and it changes the frequencies of alleles in the population randomly.
In our case, the fishes caught by the fishing net are not going to reproduce and pass on their genetic material, therefore changing the genetic structure of the next generation. This event is solely random ( there is no mechanism of selection which individual fish is going to be caught).
Answer:
If the genes were linked, the phenotypic and genotypic ratios would be different from 1:1:1:1. The observed proportions in the F1 would be different than the expected ones if genes would assort independently.
Explanation:
Due to technical problems, you will find the complete answer and explanation in the attached files