Which of the following describes a Class A IP address?

A.
The last octet is between 1 and 128 with a subnet mask of 255.0.0.0

B.
The first octet is between 1 and 128 with a subnet mask of 255.255.255.0

C.
The first octet is between 1 and 128 with a subnet mask of 255.0.0.0