Read the following statements regarding the various techniques used in cancer detection:

(i) Cancer detection is based on biopsy and histopathological studies of the tissues and the blood and bone marrow tests for increased cell counts in case of leukemia.

(ii) In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope by the pathologist.

(iii) 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.

(iv) Computed tomography uses strong magnetic fields and non-ionising radiations to detect physiological changes in living tissues.

(v) Early detection of cancer is essential as it allow the disease to be treated successfully.

Which of the following statement are incorrect?