Here are the suggestions for each blank based on the passage:

1. **B. amazing** (The computer is undoubtedly one of the most amazing important inventions of the twentieth century.)
2. **A. usage** (The usage of the computer has not been entirely problem-free.)
3. **C. astonishing** (They think that computers themselves are astonishingly too powerful.)
4. **D. operation** (If a computer is in operation, then the information it is storing can be lost.)
5. **B. affected** (If a computer program has an affected in it.)
6. **D. error** (The computer’s calculations can be seriously in error.)
7. **C. introduction** (Although computer systems are carefully designed to prevent unauthorized people using them, computer introduction do happen.)
8. **A. chaos** (Hackers can cause chaos by making unauthorized changes.)
9. **C. stealing** (Or stealing monetary information.)
10. **A. transferring** (They can even steal money by transferring it from one bank account to another.)

So, the completed passage would read as follows:

The computer is undoubtedly one of the most **amazing** and important inventions of the twentieth century. Boring or time-consuming jobs which, in the past, would have been carried out by hundreds of workers can now be done by one small computer. However, the **usage** of the computer has not been entirely problem-free. Many people feel that we are already too dependent on computers. They think that computers themselves are **astonishingly** too powerful, and that people are no longer in control of them.

One of the problems with a computer is that, like any other machines, it can break down. If a computer is **in operation**, then the information it is storing can be lost. If a computer program has an **affected** in it, the computer's calculations can be seriously in **error**. A faulty program in a hospital or police computer could cause terrible mistakes.

The other problem with computers is security. Although computer systems are carefully designed to prevent unauthorized people using them, computer **introduction** do happen. Illegal computer users, known as "hackers," have found ways to gain access to company, and even governmental, computer systems. Hackers can cause **chaos** by making unauthorized changes to a system or **stealing** information. They can even steal money by **transferring** it from one bank account to another.