The number 0 (zero) is required for

Options

A. transistor
B. abacus
C. computer
D. calculator

Explanation

To solve the question regarding the importance of the number zero, we can break it down into several steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Zero**:
- Zero is a numerical digit that represents the absence of a quantity. It plays a crucial role in mathematics and computing.

2. **Binary System**:
- In digital communication and computer science, the binary system is fundamental. This system uses only two digits: 0 and 1.

3. **Role of Zero in Binary Code**:
- In binary code, 0 typically represents the "off" state, while 1 represents the "on" state. This binary representation is essential for digital circuits and computer operations.

4. **Digital Communication**:
- Digital communication relies on binary code to transmit data. The presence of 0 and 1 allows for the encoding of information, enabling computers to process and communicate effectively.

5. **Conclusion**:
- Therefore, the number zero is essential for digital communication, as it forms the basis of binary code used in computers.

### Final Answer:
The number 0 (zero) is required for digital communication, particularly in the binary system where it represents the "off" state.

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