Respuesta :
The body's first line of defence against infection is White blood cells
The body’s first line of defense against infection is white blood cells. So, the correct option is A.
What is infection?
Infection may be defined as the process of invasion and growth of microorganisms inside the body of living entities and causes harm.
White blood cells play a key role in protecting the body from infections and defend it with other foreign substances. It is the first line of defense in case of infection.
Therefore, it is well described above.
To learn more about White blood cells, refer to the link:
https://brainly.com/question/907662
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