NTP is the protocol used for:

• A. Synchronizing clocks of computer systems and devices.
• B. Encrypting data in transit.
• C. Dynamic routing in networks.
• D. Managing access control lists.

Answer: (A)

NTP is used to keep clocks in sync across machines. When systems share timestamps for logs, events, and audits, having their clocks aligned prevents confusion in incident response and reporting, which is crucial for PCI DSS logging and monitoring. NTP works by querying trusted time sources and adjusting local clocks to match reference time, so every device reflects the same time.

This protocol doesn’t provide encryption for data in transit—that’s the job of encryption methods like TLS or IPsec. It also isn’t about routing decisions, which are handled by routing protocols, nor about controlling traffic through access control lists.