Final answer:
Systems theory proposes that family dynamics are best understood through the lens of circular causality, which considers the multi-directional influences within complex family systems. Option number b is correct.
Step-by-step explanation:
Systems theory argues that complex systems, such as families, are better conceptualized in terms of circular causality rather than linear causality.
This perspective aligns with contemporary views that reject rigid and conventional assumptions of early "stage" theories in sociology. These traditional stage theories have been criticized for failing to account for the diversity and fluidity of family forms, and for making generalized claims about family life without considering variations in gender, ethnicity, culture, and lifestyle. In contrast, circular causality within systems theory implies that family dynamics are multi-directional and continuously influencing each other, a concept which better captures the complexity and evolving nature of family structures and relationships in modern society.