IGCSE Computer Science Practice Test

In parallel data transmission, an internal clock is crucial because it ensures that all bits in a byte arrive at their destination in a synchronized manner. This synchronization is vital for maintaining the correct order of bits, as multiple bits are sent simultaneously over different channels. Without a clock, there could be timing discrepancies, leading to bits being misaligned, which would result in data corruption or incorrect interpretation of the received data.

The internal clock serves as a timing reference that dictates when each bit should be transmitted and when it is expected to be received. This guarantees that the data remains in the correct order, which is essential for accurate data processing and interpretation by the receiving system.

Other options, while they might sound plausible, do not accurately reflect functions provided by the internal clock in the context of parallel data transmission. For instance, the internal clock does not allow for unlimited transmission distance or provide security features like encryption. Additionally, while the clock's timing can influence data processing efficiency, it is not primarily designated for speeding up CPU operations. Its main role is about synchronization and order of data arrival.