Answer:
D. Sequence number
Explanation:
The sequence number facilitates the keeping track of many segments. This enables it to determine which segments out of many in which it should be in. The sequence number field is usually 32 bits.
Sequence numbers are used in transmitting data because of their importance. Since data is transmitted in packets, they can be lost and as such the receiver uses the sequence numbers to reorder them.
The system software consists of the programs that control or maintain the operations of the computer and its devices.
Answer:
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