What is the author’s main purpose in the text?

A
to encourage people to get vaccinated for the influenza virus to avoid the symptoms
B
to show how the immune system actually does more damage than the virus itself
C
to explain to people that the worse they feel during the flu, the faster they’re healing
D
to explain why people feel so horrible when they’re infected with the influenza virus

i think b

Explanation:

Hope this helps :)

hm, switch the relative; nominative and indefinite; objective ? not too bright in the knowledge of the english.

the pronoun reference replaces a noun, but you have to make sure there's no room for confusion.

in the first sentence "her" could be referring to shely or to the sister. the answer there is "shelly called her sister and told her about the new baby."

in the second sentence "it" could be referring to the roof or the floor. the answer there is "since the roof leaks on the family room floor, we need to repair the roof."