Which information helped scientists determine the survival probability of a population?

The level of genetic variation in the population
The feeding habits of an individual in the population
The number of offspring of an individual in the population
The existence of natural selection in the population

The level of genetic variation in the population, the number of offspring of an individual in the population, and the existence of natural selection in the population all helped scientists determine the survival probability of a population. The feeding habits of an individual in the population may provide some insight but are not as critical in determining survival probability.