<img src="https://nimg.ppkao.com/2018-07/xiashuhui/2018072314222285656.jpg?sign=f77d07d6a31cc70140312a90b834cf2c&t=62d0872c" /><br /> What is the under lying cause of this problem?()<br />
A、A remote physical layer problem exists.
B、The host NIC is not functioning.
C、TCP/IP has not been correctly installed on the host.
D、A local physical layer problem exists.