Which of the following is a social sign of substance dependency in youth?

When considering social signs of substance dependency in youth, a change in attire can be a significant indicator. Adolescents who begin to engage in substance use may alter their appearance as part of a broader shift in behavior and identity. This change might reflect an attempt to fit in with new peer groups or could be a sign of neglect in personal grooming and hygiene due to increased focus on substance use.

In contrast, increased grades indicate improvement in academic performance, which is generally not associated with substance dependency. More family time suggests positive engagement and support, often seen in healthy family dynamics rather than dependency situations. Consistent friendships indicate stable social relationships, which can be undermined in cases of substance dependency, as youth may start to isolate themselves or associate more with peers who share similar substance use behaviors. Thus, the noticeable change in attire stands out as a relevant social sign of substance dependency.