The correct option is D There are vaccines against tetanus and cancer.
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The immune system remembers the microbe it encounters and develops the immunity against it, along with creating the memory of that specific microbe. A weakened or dead sample of the pathogen is inserted in the body as a vaccine. Next time the body encounters the same microbe, the immune system reacts with more vigour, due to the previous memory and destroys it much more quickly.
There are vaccines for diseases like against tetanus, diphtheria, whooping cough, measles, polio but NOT for cancer.