Answer:
The correct answer is ''portrait orientation''.
Step-by-step explanation:
To begin with, the orientation of a paper refers to the way in which that paper is written. This orientation could be landscape or portrait and the most common one to use in letters is the second one, the portrait orientation.
Secondly, the portrait orientation refers to the vertical orientation of the paper in order to write the letter in that form. Moreover if the person uses this type of orientation, that it very common in letters, then the paper will has its height longer than the width because that would help the writer to order the paragraphs from higher to lower in the text with the purpose of giving them structure regarding introduction, body and closure.