Because UDP is a connectionless protocol: (Select 2)

A.
UDPrecvfrom() and write() scanning will yield reliable results

B.
It can only be used for Connect scans

C.
It can only be used for SYN scans

D.
There is no guarantee that the UDP packets will arrive at their destination

E.
ICMP port unreachable messages may not be returned successfully

Explanation:
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