Which of the following is correct about the TCP connection?

The correct option is: Client and server initiate closing connection at same time.

In a standard Transmission Control Protocol (TCP) connection termination, either of the two connected endpoints (the client or the server) can actively initiate the closing sequence. This is typically done through a four-way handshake. However, TCP is designed to handle a scenario known as a simultaneous close, where both the client and the server initiate the closing of the connection at the same time.

When a simultaneous close occurs, the sequence of events is as follows:
1. Both the client and the server decide to close the connection simultaneously and send a FIN segment to each other.
2. Upon sending the FIN segment, both endpoints transition from the ESTABLISHED state to the FIN_WAIT_1 state.
3. When each side receives the FIN segment sent by the other side, they acknowledge it by sending an ACK segment and transition to the CLOSING state.
4. Once both sides receive the final ACK segments, they transition through the TIME_WAIT state before finally closing the connection completely.

Therefore, TCP fully supports and allows a scenario where the client and the server initiate the closing process at the same time.