Answer:
A. antibody
Explanation:
Antibodies are glycoproteins, also called immunoglobulins, whose main function is to ensure the body's defense. These defense glycoproteins act in different ways to prevent an invasive particle from causing harm to health. They can be found in plasma, cytoplasmic compartments, the surface of some cells, interstitial fluid, and even breast milk
Antibodies are produced by the innate immune response and have the ability to recognize an invading organism that has already been received by an individual's body. When this invading organism returns, antibodies can stop it more quickly and easily. An example of this can be seen in the question above, where a girl who had already been infected with chicken pox as a child was able to get rid of chicken pox more quickly.
