Final answer:
The individual described is most likely experiencing Social Anxiety Disorder, and the recommended treatments are Selective serotonin reuptake inhibitors and psychotherapy, particularly cognitive-behavioral therapy.
Step-by-step explanation:
The diagnosis for someone who keeps to themselves and does not interact with peers due to fear of being laughed at is likely Social Anxiety Disorder. The appropriate treatment options for Social Anxiety Disorder typically include Selective serotonin reuptake inhibitors (SSRIs) and/or various forms of psychotherapy, which may involve cognitive-behavioral therapy (CBT) techniques. This disorder is characterized by persistent fear of social or performance situations in which embarrassment may occur and leads to significant impairment or distress. SSRIs are a class of medications that can help reduce symptoms by altering serotonin levels in the brain, while psychotherapy can provide strategies to cope with anxiety-provoking situations.