Choose the number or group of numbers which is different from others.
A13
B17
C23
D37
A13
B17
C23
D37
Related Questions:
Based on the English alphabetical order, three of the following four letter-cluster pairs are alike in a certain way and thus form a group. Which letter-cluster pair DOES NOT belong to that group?
(Note: The odd one out is not based on the number of consonants/vowels or their position in the letter-cluster.)