In Choose odd Letter Group type questions, usually five groups of letters are given. Four of them are similar to each other in some manner while one is different and this is to be chosen by the candidate as the answer.
BdEg , KmNp , PrSu , TwXz
In all other groups, the first, second and third letters are respectively moved two,
one and two steps forward to obtain the second, third and fourth letters respectively.