At high doses, ______ kills cancer cells or slows their growth by damaging their DNA. Cancer cells whose DNA is damaged beyond repair stop dividing or die. When the damaged cells die, they are broken down and removed by the body.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. Radiation therapy
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The correct answer is Radiation therapy.
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Radiation therapy uses high doses of radiation to kill cancer cells or slow their growth by damaging their DNA.
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When DNA is damaged beyond repair, cancer cells stop dividing or die.
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The body then naturally removes these dead or damaged cells.
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Radiation therapy is often used either alone or along with chemotherapy or surgery, depending on the type and stage of cancer.
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It is a targeted treatment, minimizing harm to surrounding healthy tissues.
Explanation of Other Options:
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Chemotherapy uses drugs to kill cancer cells, but not by radiation.
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Surgery physically removes tumors but doesn’t involve DNA damage.
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Physiotherapy is used for physical rehabilitation, not cancer treatment.
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Therefore, only radiation therapy fits the description of using high doses to damage DNA and kill cancer cells.