1) Go through the standard Chrome OS login screen (you'll need to setup a network, etc) and get to the web browser. It's OK if you login as guest.
2) Press [ Ctrl ] [ Alt ] [ T ] to get the crosh shell.
3) Use the shell command to get the shell prompt.
Answer:
The answer is likely C. "Can be used by CSS to apply the same formatting to more than one HTML element."
Explanation:
Given that the name of the attribute is "class," it sounds like the kind of code that would be applied to multiple elements intended to display something a specific way.
Qualification:
I've invested hours of my time into learning HTML, but I've never dealt with the "class" attribute. So, maybe take my answer as a grain of salt.
Wrong..............................................