假设两个主机使用TCP连接来传输大文件。对于TCP连接，以下哪个语句是False?
1. If the sequence number of a segment is m, then the sequence
number of the subsequent segment is always m+1.
2. If the estimated round trip time at any given point of time
is t sec, the value of the retransmission timeout is always
set to greater than or equal to t sec.
3. The size of the advertised window never changes during the
course of the TCP connection.
4. The number of unacknowledged bytes at the sender is always
less than or equal to the advertised window (A)仅3
(B)仅1和3
(C)仅1和4
(D)仅2和4答案： (B)
说明：段的TCP序列号是段中第一个字节的字节号。例如，如果该段包含500个字节(从1000到1499)，则该段的序列号将为1000，而下一个段的序列号将为1500。
当接收方的应用层处理TCP数据时，接收方窗口改变。
这个问题的测验