Final answer:
The population changes in mice could be due to genetic drift or other factors such as a) environmental changes or predation. Without more information, the future appearance of the population after 40 generations d) cannot be accurately predicted.
Step-by-step explanation:
The changes in the population of mice mentioned in the question could be caused by various factors including environmental changes, genetic mutations, predation, and random chance. One of the factors, genetic drift, is a key element that can change a population's allele and genotype frequencies simply by chance, not due to any advantage conferred by genetically-encoded traits. For example, environmental factors such as a storm could disproportionately kill certain individuals carrying a specific allele, thus affecting genetic diversity. Likewise, changes in food availability or levels of predation can also influence survival and reproduction, leading to changes in genetic variation.
Without additional information, it is impossible to accurately predict how the mouse population would look after 40 generations. Factors such as environmental changes, predation, availability of food, genetic mutations, or random events can all influence the future of the population. Therefore, the answer is that we cannot predict without more information.