Read the following passage carefully and answer the given questions.
Cancerous cells just continue to divide giving rise to masses of cells called tumors. Benign tumors normally remain confined to their original location and do not spread to other parts of the body and cause little damage. The malignant tumors, on the other hand are a mass of proliferating cells called neoplastic or tumor cells. Transformation of normal cells into cancerous neoplastic cells may be induced by physical, chemical or biological agents. Ionising radiations like X-rays and gamma rays and non-ionizing radiations like UV cause cancer. Cancer-causing viruses are called oncogenic viruses which have viral oncogenes. The substances to which an immune response is produced are called allergens. The antibodies produced to these are of IgE type. Common examples of allergens are mites in dust, pollens, animal dander, etc. The primary lymphoid organs are bone marrow and thymus. The secondary lymphoid organs provide the sites for interaction of lymphocytes with the antigen, which then proliferate to become effector cells.
Which one of the following antibodies are produced in response to the allergens?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → IgE
Allergy is an exaggerated response of the immune system to a harmless substance in the surroundings, such as pollen, dust mites or animal dander. Such a substance is called an allergen. Mast cells release histamine and serotonin, which cause sneezing, watery eyes and a running nose.
Option (1) IgA — Incorrect. IgA is the antibody present in secretions such as colostrum, the first milk. It protects the infant.
Option (2) IgG — Incorrect. IgG is the most plentiful antibody in the blood and fights infections. It can also cross the placenta from mother to foetus.
Option (3) IgE — Correct. In an allergy the body makes antibodies of the IgE type against the allergen. These cause the release of chemicals such as histamine and serotonin from mast cells, which bring the symptoms.
Option (4) IgM — Incorrect. IgM is the first antibody produced when an infection begins. It is not the allergy antibody.
Note 1: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
Note 2: The same question was also asked in CUET (UG) 2026 on 25-05-2026 (Slot 1), and a similar question in CUET (UG) 2026 on 21-05-2026 (Slot 2).