From the given anagrams select the odd one out.

In this alphanumeric anagram series, each item pairs two letters with a trailing number. In a correctly-formed item, the trailing number equals the alphabetical position of the second letter (A=1, B=2, ... Z=26). To find the odd one out, check whether this letter-to-number correspondence holds for every item -- the one item where it fails is the exception.

Checking against the first letter of each pair (A, D, H, K) shows no fixed relationship to the trailing number, confirming the intended rule is the second-letter check. Under that rule, exactly one item -- the one with trailing number 18 -- fails to match; every other item matches its second letter's position exactly.

Since KP18 breaks the pattern that AE5, DF6 and HN14 all satisfy, KP18 is the odd one out.