Alexis most enjoys talking and socializing with friends late in the evening. her mother, however, is most energized for social interactions about an hour after breakfast. this difference between alexis and her mother is best explained by the fact that age and experience tend to alter

circadian rhythm                                                          

Explanation:

Circadian rhythm: The term circadian rhythm is defined as the twenty-four-hour cycle of the physiological processes of human beings, animals, plants, etc. The circadian rhythm is an automatic process, though it can be regulated by any external cues, for example, temperature, and sunlight, etc.

Example:

1. The sleep-wake cycle.

2. The menstrual cycle.

In the question above, The difference between Alexis and her mother is best explained by the fact that age and experience tend to alter our circadian rhythm.

rain should be the answer.