(e) People who write virus programs are:
(i) People who get a thrill out of disturbing others
(ii) Unhappy people with destructive intentions
(iii) People who want to take revenge
(iv) All of the above
Answers
Answer:
The image of virus writers as intelligent kids with too much time on their hands resorting to digital vandalism to entertain themselves persists. Years ago, making such a guess about why people write viruses might have been accurate most of the time, but the world has moved on. The writers of viruses and other mobile malicious code are many and varied, and their reasons are as wide-ranging as they are themselves.
The forms of replicating mobile malicious code are multifarious, too. The most common forms are viruses, worms, and Trojans, though nonreplicating equivalents are gaining prominence as well. Cross-site scripting is an example of nonreplicating code that serves much the same purpose as self-replicating malicious code; it can affect millions without having to actually "infect" the victim's computer at all.
I can't claim to know why everybody who writes malicious code does so. I haven't met them all. I can make some generalizations about reasons people might do so, though.
There are those who, for whatever reason, just do destructive things for the sake of their destructiveness. They may be malicious narcissists, psychopaths, or just so self-centered in their impression that the whole world is against them that they will blindly lash out at anyone and everyone when they get the chance. For such people, who I believe are a thankfully rare breed, the harm they cause others has no point beyond the harm itself. They are unreasoningly destructive, and that's pretty much all there is to it. They might think they're misunderstood and want to communicate with the world by harming it in some way -- and maybe they're right, that people just don't understand them deep down. When they react to this state of affairs by maliciously setting out to harm anonymous strangers, however, I don't think I want to understand them beyond the minimum required to track them down and put a stop to their antisocial behavior. Your mileage may vary, especially if you're a criminal psychologist.
2: Do it for the Lulz
Some still do it for the "fun" of destruction. They may get a thrill out of reading news items about their work causing people trouble, or they may just take a fire-and-forget approach, creating destructive, self-replicating programs for the joy of it without much caring whether they ever see the consequences themselves. Mostly, I'm sure they find it funny to read about people being inconvenienced by what they've done. In short, some people write mobile malicious code for the same reasons vandals break windows and spray paint garage doors that belong to people they don't even know.
3: Espionage
I'm not talking about sabotage here; I'll address that later. By "espionage," I mean attempts to gather information through underhanded means for reasons other than identity fraud and other directly, criminally profitable purposes. Viruses, worms, Trojans, and even backdoors and other malicious code slipped into your software by the vendor may serve the purposes of espionage. People worry about the potential for Chinese manufactured computers having some kind of hardware backdoor built into them; conspiracy theories about commercial software vendors being required to provide backdoor access to the NSA run rampant; the government of India famously demanded that Blackberry provide universal decryption keys for all Blackberry devices sold in the country; and the NSA's Dual_EC_DRBG NIST encryption standard may itself include a backdoor of sorts, as I mentioned in What my grandmother taught me about IT security.
The answer is All of the abive