Which of the following people is at the highest risk for committing suicide?Bryan, age 16, has no one to confide in since his girlfriend broke up with him.Natalie tells her principal about the group of girls who are cyber-bullying her.Josh misses his grandfather who took his own life last year. Josh’s friends know this and are being extra-supportive.Raquel had therapy to deal with the physical abuse she suffered as a small child.

Based on the information provided, it's difficult to definitively say who is at the highest risk for suicide as it depends on a variety of factors, not all of which are mentioned here. However, we can analyze each individual's situation:

1. Bryan, age 16, has no one to confide in since his girlfriend broke up with him: Bryan is experiencing social isolation and a significant life change, which can increase his risk.

2. Natalie tells her principal about the group of girls who are cyber-bullying her: Natalie is experiencing bullying, which can increase her risk. However, she is seeking help, which is a positive sign.

3. Josh misses his grandfather who took his own life last year. Josh’s friends know this and are being extra-supportive: Josh has a family history of suicide and is experiencing grief, which can increase his risk. However, he has a supportive social network, which can help protect him.

4. Raquel had therapy to deal with the physical abuse she suffered as a small child: Raquel has a history of trauma, which can increase her risk. However, she has sought therapy, which can help reduce her risk.

Given these factors, Bryan might be at the highest risk due to his social isolation and recent breakup. However, it's important to note that this is a simplified analysis and the actual risk could be different depending on other factors not mentioned here. It's crucial to take any signs of distress seriously and seek professional help when needed.