Which term is described by 'send back to confirm'?

Which term is described by 'send back to confirm'?

• A. Echo check
• B. Check digit
• C. Automatic repeat query
• D. Checksum

Answer: (B)

The main idea is confirming data integrity with a simple error-detection addition. A check digit is a number added to a code that is computed from the other digits. When the code is read or received, the system recalculates the check digit from the data and compares it with the included check digit. If they match, the data is likely correct; if not, an error is detected, prompting a correction or retransmission. This is why this term fits a description like “send back to confirm”—the extra digit provides a quick way to confirm the data was read/transmitted accurately. Echo check would involve sending the whole data back, ARQ focuses on retransmission requests, and a checksum is a broader summing method, not a single-digit confirmation.

The main idea is confirming data integrity with a simple error-detection addition. A check digit is a number added to a code that is computed from the other digits. When the code is read or received, the system recalculates the check digit from the data and compares it with the included check digit. If they match, the data is likely correct; if not, an error is detected, prompting a correction or retransmission. This is why this term fits a description like “send back to confirm”—the extra digit provides a quick way to confirm the data was read/transmitted accurately. Echo check would involve sending the whole data back, ARQ focuses on retransmission requests, and a checksum is a broader summing method, not a single-digit confirmation.