What does CIDR notation like 192.168.1.0/24 mean?

• A.CIDR (Classless Inter-Domain Routing) notation specifies a network address and its subnet mask - /24 means the first 24 bits are the network portion and the remaining 8 bits are for host addresses, equivalent to the subnet mask 255.255.255.0
• B.The /24 means 24 computers; a network intrusion sensor placed in line reads only the first 64 bytes of each flow and drops the remainder without inspection, and it identifies malicious traffic by comparing packet arrival times against a fixed schedule published by the vendor
• C.The /24 means 24 networks; the internet protocol guarantees ordered delivery of every packet and retransmits anything that is lost, which leaves the transport layer with no responsibility beyond adding a port number to each segment before it is placed onto the wire
• D./24 is the speed in Mbps