An administrator issues the command ping 127.0.0.1 from the command line prompt on a PC. If a reply is received, what does this confirm（）。

• A、The PC has connectivity with a local host.
• B、The PC has connectivity with a Layer 3 device.
• C、The PC has a default gateway correctly configured.
• D、The PC has connectivity up to Layer 5 of the OSI model.
• E、The PC has the TCP/IP protocol stack correctly installed.