Final answer:
The valid Class B private IP address that can be used is 192.168.10.5.
Step-by-step explanation:
Among the options provided, the valid Class B private IP address that can be used is 192.168.10.5.
Class B private IP addresses range from 172.16.0.0 to 172.31.255.255 and from 192.168.0.0 to 192.168.255.255.
The options b) 10.256.0.1 and d) 300.10.0.0 are not valid Class B private IP addresses because the values exceed the range of valid octets, which is between 0 and 255.