Final answer:
The socially useful style is seen as the adaptive lifestyle in Adler's theory. It involves cooperation and contribution to society, unlike the self-serving ruling, getting, and avoiding types. Option d) is correct.
Step-by-step explanation:
In Alfred Adler's theory of lifestyles, the socially useful style is considered adaptive. This style is characterized by individuals who are cooperative, contributing positively to society, and engaging in activities that further the welfare of others as well as themselves.
In contrast, the ruling type, getting type, and avoiding type are more self-serving and reflect less adaptive approaches to social interaction. The ruling style tries to dominate others, the getting style depends on others to satisfy their needs, while the avoiding style disengages from challenging life situations, avoiding potential failure.