Which of the following involve an overactive immune system response to an external antigen?

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Quizplus · Accepted Answer

An allergy is an overactive immune system response to an external antigen, such as pollen or certain foods, resulting in symptoms such as itching, hives, and difficulty breathing. Cancer results from uncontrolled growth and division of abnormal cells, and is not typically associated with an immune system response to an external antigen. An autoimmune reaction occurs when the immune system mistakenly attacks the body's own cells and tissues, rather than foreign invaders. AIDS is caused by the human immunodeficiency virus (HIV) and weakens the immune system, making it more susceptible to infections and certain cancers. While HIV is caused by an external antigen (the virus), the overactive immune response seen in allergy is not evident in AIDS.

Which of the Following Involve an Overactive Immune System Response