What does TCP ensure regarding the packets transmitted in a network?

TCP, or Transmission Control Protocol, is designed to ensure reliable delivery of data packets over a network. The correct answer emphasizes the importance of verification in the communication process. TCP manages the transmission of packets by using a process known as acknowledgment. When a sender transmits packets, TCP requires that the recipient acknowledges the receipt of those packets. If an acknowledgment is not received within a certain timeframe, TCP will retransmit the packets. This mechanism ensures that all data sent is received accurately and in the correct order.

Additionally, TCP uses checksums to verify the integrity of the data contained in each packet, ensuring that it hasn't been altered during transmission. This reliability feature is critical for applications that require consistent and accurate data delivery, such as web browsing and file transfers. Overall, the fundamental role of TCP in verifying both transmission and receipt of packets sets it apart from other functions listed in the other options.