Final answer:
The Network Time Protocol (NTP) is the correct protocol to synchronize all devices within an IT environment. HTTP, FTP, and SNMP serve other purposes and are not primarily used for time synchronization.
Step-by-step explanation:
Cyril wants to ensure all the devices on his company's internal IT environment are properly synchronized.
The protocol that would aid in this effort is the Network Time Protocol (NTP). NTP is used to synchronize the clocks of computers to a few milliseconds of Coordinated Universal Time (UTC).
It is widely used in various types of IT environments, including enterprise networks, to ensure that events across the network are synchronized and that time-sensitive operations are coordinated.
Other protocols listed, such as HTTP, FTP, and SNMP, serve different purposes. HTTP (Hypertext Transfer Protocol) is used for transferring web pages, FTP (File Transfer Protocol) is for transferring files, and SNMP (Simple Network Management Protocol) is for managing devices on an IP network. None of these would be as effective as NTP in synchronizing time across multiple devices in an IT environment.