<span>B. nonrestrictive clause
Since it is nonrestrictive, it is not necessary and is set off by commas.
Hope this helps :)</span>
A because private must be built
This must be from a standardized test. The wording is a little confusing, but I'd say it is a metaphor. Google says the definition of metaphor is "a figure of speech in which a word or phrase is applied to an object or action to which it is not literally applicable." This is saying something <em>is</em> something, or comparing two items without using "as" or "like". Have a good night/day!
-Dylan (AKA Animus)
<em>a e s t h e t i c </em>
