Read the following statements regarding the various techniques used in cancer detection.
(i) Cancer detection is based on biopsy and histopathological studies of the tissue, and blood and bone marrow tests for increased cell counts in case of leukaemia.
(ii) In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope by a 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 fileds and non-ionising radiations to detect physiological changes in living tissues.
(v) MRI uses X-rays and ionising radiation to generate a 3-D image of the internal structure of an object.
Which of the above statements are incorrect ?

Options

A. (i) and (iii)
B. (ii) and (iv)
C. (iii) and (iv)
D. (iv) and (v)

Explanation

To determine which statements regarding cancer detection techniques are incorrect, let's analyze each statement step by step.

### Step 1: Analyze Statement (i)
**Statement:** Cancer detection is based on biopsy and histopathological studies of the tissue, and blood and bone marrow tests for increased cell counts in case of leukaemia.
**Analysis:** This statement is correct. Biopsy and histopathological studies are indeed standard methods for cancer detection, and blood and bone marrow tests are used for leukemia diagnosis.

### Step 2: Analyze Statement (ii)
**Statement:** In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under a microscope by a pathologist.
**Analysis:** This statement is also correct. The biopsy process involves cutting the tissue into thin sections, staining them, and examining them microscopically.

### Step 3: Analyze Statement (iii)
**Statement:** 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.
**Analysis:** This statement is correct. Radiography, CT, and MRI are commonly used imaging techniques for detecting internal organ cancers.

### Step 4: Analyze Statement (iv)
**Statement:** Computed tomography uses strong magnetic fields and non-ionizing radiations to detect physiological changes in living tissues.
**Analysis:** This statement is incorrect. Computed tomography (CT) uses X-rays, which are ionizing radiation, not strong magnetic fields.

### Step 5: Analyze Statement (v)
**Statement:** MRI uses X-rays and ionizing radiation to generate a 3-D image of the internal structure of an object.
**Analysis:** This statement is also incorrect. MRI uses strong magnetic fields and non-ionizing radiation, not X-rays or ionizing radiation.

### Conclusion
The incorrect statements are:
- Statement (iv): Computed tomography uses strong magnetic fields and non-ionizing radiations (Incorrect)
- Statement (v): MRI uses X-rays and ionizing radiation (Incorrect)

### Final Answer
The incorrect statements are (iv) and (v).

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