Answer:
a. The Cuckoo’s Egg
Explanation:
In "The Cuckoo’s Egg," American astronomer Clifford Stoll tells the story of his search for a computer hacker who broke into a computer in his laboratory in California after an accounting error. After months of investigation, Stoll could track the hacker's phone line and observe all his online movements, such a as accessing US military websites. Finally, the hacker was traced and found in Germany, and was indeed a KGB spy working for the Soviet Union.
