Thanks for the question! So we’re asked here for the main point of this passage. Well, what is it? Basically, the author focuses on how we shouldn’t change copyright law at the end of the passage, and everything else builds up to that conclusion. So that's the main point of the passage, it's why the passage was written.
So now let’s take a look at (A), which tells us that since distribution of a document on a Web page is controlled by the author of the page and not the person who creates a link, that shouldn’t be copyright infringement. And so that basically falls in line with the main point, that such a case shouldn’t be considered copyright infringement, since we shouldn’t change the copyright laws.
Now let’s take a look at (E), which tells us that the main point is that maintaining a free exchange of ideas on the Web offers more benefits than changing copyright laws. But the thing is that (E) tells us that the radical alteration of copyright laws aren’t aimed at restricting the Web’s growth, and for something to be the main point, it has to be true and the main point. And this isn’t even true based on the passage. Also, the main point isn’t just that the benefits outweigh the cons. It’s that because the benefits outweigh the cons, the laws shouldn’t be changed. That’s another step the passage takes that (E) doesn’t.
Hope this helps! Feel free to ask any other questions that you might have.
