Which of the following diagnostic tests is commonly used to assess immune function in individuals suspected of having an immunodeficiency disorder?

Explanation: The correct answer is b. Genetic or inherited defects. Immunodeficiency disorders are primarily caused by genetic mutations or defects that result in a weakened or impaired immune system.

Incorrect choices:

a. While environmental factors can contribute to the development of secondary immunodeficiency disorders, they are not the primary cause of most immunodeficiency disorders.

c. Autoimmune reactions are not the primary cause of immunodeficiency disorders. Autoimmune disorders involve the immune system attacking the body's own tissues, not a deficiency in the immune system.

d. Excessive production of white blood cells is not the primary cause of immunodeficiency disorders. In fact, immunodeficiency disorders are characterized by a deficiency or impairment of white blood cells, which are essential components of the immune system.

Explanation: The correct answer is c. Frequent and severe infections. One of the hallmark features of immunodeficiency disorders is an increased susceptibility to infections. Individuals with immunodeficiencies may experience frequent and severe infections, including bacterial, viral, and fungal infections.

Incorrect choices:

a. Excessive inflammation at the site of infection is not a common clinical manifestation of immunodeficiency disorders. Immunodeficiencies are characterized by a weakened immune response, which may result in a reduced inflammatory response to infections.

b. Hyperactive immune response to allergens is seen in allergies and autoimmune disorders, not immunodeficiency disorders.

d. Immunodeficiency disorders are characterized by a lack or dysfunction of specific immune components, such as B cells or T cells, leading to a decreased production of antibodies, not increased.