Question

Which statement correctly describes DNS's transport-layer usage?

A DNS always uses TCP port 53 for reliability since domain resolution is a critical service
B DNS uses UDP port 43 for queries and TCP port 53 only for recursive queries
C DNS uses UDP for zone transfers and TCP for standard queries
D DNS uses ICMP for name resolution and TCP for zone transfers
E DNS uses UDP port 53 for standard queries but switches to TCP port 53 for zone transfers and responses exceeding the UDP size limit
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