Respuesta :
The answer is;
The population size is now not large enough.
This is referred to as a bottleneck effect. Due to the calamity wiping out a huge chunk of the population, the variation in the population reduces. The genetic drift is, therefore, more pronounced on the small population than big population due to reduced sampling. The reduced genetic variation makes the population vulnerable to environmental changes because natural selection will not find a wide variation of genotype to act upon.
Answer:
If I am correct, C, "The population size is now not large enough." would be the correct answer.