Let's analyze the letter pairs based on their positions in the alphabet:
J (10), L (12) — difference 2
F (6), T (20) — difference 14
H (8), O (15) — difference 7
E (5), Z (26) — difference 21
Check for common similarity:
Pairs FT, HO, and EZ both have letters with positional differences that are multiples of 7 (14, 7, 21 respectively).
Pair JL differs by 2, which does not follow this pattern.
Hence, JL is the odd one out.