Final answer:
Aggression is the most predictive type of social behavior leading to peer rejection among children, as it typically results in a negative and hostile social environment.
Step-by-step explanation:
The most predictive type of social behavior of rejection by peers among children is aggression. Aggression includes behaviors that are intended to cause harm or pain to others, and can manifest as either physical harm or psychological abuse, such as bullying. Research has indicated that children who display aggressive tendencies, whether through physically harming others or through social means like spreading rumors, are more likely to be rejected by their peers. This is because such behaviors create a negative and hostile social environment, which peers tend to avoid. On the other hand, children who are emotionally reactive or different in certain ways, such as cognitively or physically, may also attract negative attention and potentially become targets for bullying.