Which of the Following Statements Are NOT True Regarding the TCP

Which of the following statements are NOT true regarding the TCP sliding window protocol? (Multiple Choice)

A) The initial window offer is advertised by the sender
B) If the retransmission timer expires without the sender receiving an ACK message, the receiver retransmits the packet to the sender.
C) The size of the sliding window can only increase or stay the same
D) It allows the transmission of multiple frames before waiting for an acknowledgment
E) The receiver is required to acknowledge the data packets transmitted by the sender
F) The sender need not transmit a full window's worth of data