Answer the following question: Read the following article and answer the question. Article: It appears that the police now have a device that can read license plates and check if a car is unregistered, uninsured or stolen. We already know that National Security Agency can dip into your Facebook page and Google searches. And it seems that almost every store we go into these days wants your home phone number and ZIP code as part of any deal. So when Edward Snowden -- now cooling his heels in Russia -- revealed the extent to which the NSA is spying on Americans, collecting data on phone calls we make, it's not as if we should have been surprised. We live in a world that George Orwell predicted in 1984. And that realization has caused sales of the 1949, dystopian novel to spike dramatically upward recently -- a 9,000% increase at one point on Amazon. com. Comparisons between Orwell's novel about a tightly controlled totalitarian future ruled by the everywhere-present Big Brother and today are, in fact, quite similar. Here are a few of the most obvious ones. Telescreens -- in the novel, nearly all public and private places have large TV screens that broadcast government propaganda , news and approved entertainment. But they are also two-way monitors that spy on citizens, private lives. Today websites like Facebook track our likes and dislikes, and governments and private individuals hack into our computers and find out what they want to know. Then there are the ever-present monitoring cameras that spy on the ordinary people as they go about their daily routine. The endless war -- In Orwell's book, there's global war that has been going on seemingly forever, and as the book's hero, Winston Smith, realizes the enemy keeps changing. One week we're at war with Eastasia and friends with Eurasia. The next week, it's just the opposite. There seems little to distinguish the two opponents, and they are used primarily to keep the people of Oceania, where Smith lives, in a constant state of fear, thereby making disagreement unthinkable -- or punishable. Today we have the so-called war on terror, with no end in... Question: What caused 1984 to sell well on Amazon.com? Answer:

Available choices:
a). The similarities between the world we live in and that of 1984..
b). The surprise at how Americans are spied on by the government..
c). The fact that authorities have access to our personal information..
d). The worry that our government agencies can monitor our phones..
Answer:
a).