Which of the following techniques are commonly used for early detecti…

The correct answer is Option (3) → (A), (B) and (C) only

(A) Biopsy and histopathological studies — Correct. A pathologist looks at the cells of the suspected tissue under a microscope. Cancer cells look different from normal cells. For leukaemia (blood cancer), blood and bone marrow tests are used instead.

(B) Radiography (x-rays) — Correct. X-rays show a tumour inside the body without cutting it open. Computed tomography (CT) uses X-rays to build a three-dimensional image of the inside of an organ.

(C) MRI (Magnetic Resonance Imaging) — Correct. MRI uses strong magnetic fields and non-ionising radiation to find changes in living tissue accurately, so it can locate cancers of internal organs.

(D) Electrocardiogram (ECG) — Incorrect. An ECG records the electrical activity of the heart. It is used to study heart disease, not to find cancer.

Note: The original NTA paper printed Option (1) and Option (4) the same, ‘(A), (B), (C) and (D) only’. Option (4) has been changed to ‘(B), (C) and (D) only’, so that the four options are different. The answer is not affected.

NCERT Extract:
Cancer – “… Cancer detection and diagnosis : Early detection of cancers is essential as it allows the disease to be treated successfully in many cases. Cancer detection is based on biopsy and histopathological studies of the tissue and blood and bone marrow tests for increased cell counts in the case of leukemias. In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope (histopathological studies) by a pathologist. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs.”