Answer:
The author's purpose suggested by the text is:
C. to inform readers about an infectious disease called mononucleosis.
Step-by-step explanation:
Let's summarize the passage by dividing it into topics:
- there is a disease called mononucleosis;
- the virus that causes it is the Epstein-Barr;
- it spreads through saliva;
- the symptoms include fatigue, fever, sore throat, etc.;
- a blood test can confirm the disease;
- the symptoms last a few weeks.
As we can see, the passage gives us some general knowledge about the disease. It does not focus on how the virus was discovered at all. Even though it mentions the symptoms of mono, it is incorrect to say that the passage's purpose is to describe how it feels to have the disease. That is not its focus, it is just one of the many topics it discusses. Therefore, the best option is letter C:
C. to inform readers about an infectious disease called mononucleosis.