The correct answer is:
a) Problem and solution
In composition, a problem and solution format is a type of text where you can identify a problem and proposing one or more solutions. A problem-solution essay is a type of argument. "This kind of texts involve argumentation in that the writer seeks to convince the reader to take a particular course of action. In this case the writer is trying to convince you to own a pet.
B I hope its right, im not sure, good luck
