Question

generally, why do writers employ satire?
to warn their readers about something they consider a threat
to warn their readers about something they consider as safety.
to warn their readers about product guarantee.
to warn their readers about product warranty.

Explanation:

Satire is a literary device used to expose and criticize foolishness and corruption of an individual or a society by using humor, irony, exaggeration, or ridicule. Writers often use it to draw attention to issues they see as threats. The other options about safety, product - guarantee, and product - warranty are not the main reasons for using satire.

Answer:

To warn their readers about something they consider a threat