Sara has recently joined a sports club and her parents are noticing some changes in her behavior. Which of these indicates that Sara might be using performance-enhancing drugs?

Increased aggression can be a behavioral sign of using performance-enhancing drugs, especially anabolic steroids, which may affect mood and impulse control. Stunted growth, skin infections, and high blood pressure can also be associated with some drug use, but among the choices, increased aggression is the behavior change described most directly.

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