Final answer:
Parental-investment theory can be used to explain differences in rates of child abuse based on biological children versus stepchildren, as well as the influence of parenting styles and children's temperament on child abuse.
Step-by-step explanation:
Parental-investment theory can be used to explain differences in rates of child abuse perpetrated against biological children versus stepchildren. According to research, young parents and teenage mothers are more likely to abuse their children than older parents, and children born to mothers who are fifteen years old or younger are twice as likely to be abused. Furthermore, parenting styles and children's temperament also play a role in child abuse, as easy children tend to elicit warm and responsive parenting, while difficult children may challenge their parents and evoke irritation.