Which of the following option can be used to change page-size and margins?

Page layout is the part of graphic design that deals in the arrangement of visual elements on a page. It generally involves organizational principles of composition to achieve specific communication objectives. It may be used to change page-size and margins.
The high-level page layout involves deciding on the overall arrangement of text and images, and possibly on the size or shape of the medium. It requires intelligence, sentience, and creativity, and is informed by culture, psychology, and what the document authors and editors wish to communicate and emphasize. Low-level pagination and typesetting are more mechanical processes. Given certain parameters - boundaries of text areas, the typeface, font size, and justification preference can be done in a straightforward way.