Well, we know that a lot of the ancient civilizations were first-handedly affected by disease. For example, Native Americans were severely impacted by the spread of pestilence. 90% of their population was completely killed off. I think that would be enough to concern them, don't you think? :P
Answer:
The correct answer is b. Immunogens
Explanation:
Immunogens are the antigens that can trigger the immune response in the body once gets inside the body. Any antigen having capacity to excite a immune response against them is called immunogens but not every antigen is immunogen.
An antigen is called immunogen when it has some characteristic features like foreignness, high molecular weight and chemical complexity. An immunogen can initiate both innate and adaptive immune response. Adaptive immune response is memory based and very specific for any particular immunogen.
Some common immunogens are: bacteria, virus, drugs, chemicals, dust, toxins.
It’s an example of disenfranchised grief
Lack of trees , plants , shrubs and herbs