Which of the following is not a way to acquire background knowledge about the cultural context of a text?

a.
looking at pictures and reading captions

b.
paying attention to footnotes

c.
skipping every other paragraph while browsing a text

d.
reading the introductory material

C skipping every other paragraph while browsing a text

This is really not an answer for gaining any information let alone background information. Often the introductory material gives background information about the text and is usually thought to be important to help the reader better understand the text. This is also true of pictures and footnotes. They are used to help clarify information and give context the reader may not already know.

that's conceptually impossible.

if i wrote it, it wouldn't be a 'shakespeare' sonnet.