Which is the correct netmask?

Your system is assigned an IP address object 192.168.0.222/24. However, the net
maskexpressed as four octetsis required. Which is the correct netmask?

A.
255.0.0.0

B.
255.255.0.0

C.
255.255.255.0

D.
255.255.255.24

E.
255.255.255.255

Explanation:
A 24-bit network mask is expressed as 255.255.255.0.

Reference: http://www.subnet-calculator.com/