Why Does It Make Sense That Mp3 Players, Like IPods

Why does it make sense that mp3 players, like iPods, would replace the compact disc in a postmodern economy?

A) There are limits to the number of CDs you can sell to any one person, but more "ephemeral" products like mp3s and downloaded movies can be sold faster and more often.
B) Mp3 players are better designed than CDs and make use of the same technologies (the computer chip) that are driving the information economy.
C) Mp3 players are less portable and mobile than CDs.
D) Mp3 players allow more control of the dissemination of information, which undermines the constitutional rights of the average citizen to have her voice heard.
E) Mp3 players could only exist after the removal of government restrictions on the media industry allowed companies to gain control of ever-larger chunks of the media market.