Which one of the following characteristics observed in a teenage boy should always alert the nurse to the possibility of suicide?

Reasoning: Choice A reason: A history of torturing or abusing animals is a clinical red flag often associated with conduct disorder or the development of antisocial personality traits. While it indicates significant psychological disturbance and a risk for interpersonal violence, it is more strongly correlated with outward aggression rather than the internalizing pathology of self-harm. Choice B reason: Threatening to cause harm to peers is an indicator of homicidal ideation or externalized behavioral dysregulation. While some individuals may harbor both homicidal and suicidal thoughts, a threat toward others is categorized under "duty to warn" protocols rather than being the primary diagnostic indicator for an imminent suicide risk. Choice C reason: Adolescent males who identify as LGBTQ+ face significantly higher rates of victimization, bullying, and social isolation. When combined with a clinical history of depression, the risk for suicide increases exponentially. Research indicates this demographic is at a much higher statistical risk for completed suicide compared to their heterosexual peers due to minority stress. Choice D reason: While the age range of 15 to 19 years represents a high-risk developmental period for suicide, age alone is a demographic variable rather than a specific alerting characteristic. It lacks the clinical specificity of a comorbid mental health diagnosis or a vulnerable social identity that would trigger an immediate, high-priority suicide assessment.