What is the most likely reason for the first ping having a success rate of only 60 percent?

Refer to the exhibit.

The network administrator is testing connectivity from the branch router to the newly installed application server.

What is the most likely reason for the first ping having a success rate of only 60 percent?
A . The network is likely to be congested, with the result that packets are being intermittently dropped.
B . The branch router had to resolve the application server MAC address.
C . There is a short delay while NAT translates the server IP address.
D . A routing table lookup delayed forwarding on the first two ping packets.
E . The branch router LAN interface should be upgraded to FastEthernet.

Answer: B

Explanation:

Initially the MAC address had to be resolved, but later on it was confirmed to ping went straight away