Answer:
a. the spacing effect
Explanation:
The spacing effect: In psychology, the term spacing effect was first introduced by a German psychologist named Hermann Ebbinghaus, and is defined as the phenomenon which suggests that the long-term memory of an individual is increased when the learning related to different events are being spaced apart in interval of time instead of occurrence in immediate succession.
Example: Remembering items in a list.
In the question above, the given statement illustrates the spacing effect.
The answer is midlife crisis. This is a period of psychological stress taking place in middle age supposed to be caused by a physical, occupational or domestic occasion as menopause, decrease of physical ability, job loss or departure of children from the home and contains frustration, panic and emotional state of pointlessness sometimes causing radical and frequently illness which counseled variations of lifestyle.