Question

An author's purpose is often to get us to think more deeply about a topic. Rosen does this in her article when she writes

A.) As with any new technological advance, we must consider what type of behavior online social networking encourages.
B.) By contrast, today's social networking sites organize themselves around metaphors of the person, with individual profiles that list hobbies and interests.
C.) Indeed, media coverage of social networking sites usually describes them as vast teenage playgrounds—or wastelands, depending on one's perspective.
D.) The Delphic oracle's guidance was know thyself. Today, in the world of online social networks, the oracle's advice might be show thyself.

Answer 1

I'd sat choice A most explicitly "makes us think more deeply about a topic." In fact, Rosen incites us (the readers) explicitly, writing: "we must consider what..." thus making us "think." 
With this, however, one may argue that choice D incites us implicitly, saying: "the oracles advice might be show thyself." By using the phrase "might be", Rosen establishes an unsure position, one which could, if further discussion warranted it, potentially change. 
If you need further clarification, ask for it!

Answer 2

Answer:

A.) As with any new technological advance, we must consider what type of behavior online social networking encourages.

Explanation:

Rosen is directly inviting the readers to reflect on the fact that we do not consider enough what type of behavior social networking encourages, the fact of being behind of a screen and being able to interact with other people makes for an environment where people has little to no consequences of what they are syinf or doing in social media.