Find the odd from the given alternatives.

In each of the following questions, certain pairs of words are given, out of which the words in all pairs excepts one, bear a certain common relationship. Choose the pair in which the words are differently related.

In the following question, select the odd letters from the given alternatives.

Choose the related word/letters/number from the given alternatives.
 AF : BE : : ? : DH

Three of the following four letter-clusters are alike in a certain way and one is different. Pick the odd one out.

Four letter clusters have been given, out of which three are alike in some manner, while one is different. Choose the odd one.

Four letter-cluster have been given out of which three are alike in some manner, while one is different. Choose the odd one.

Three of the following four letter-clusters are alike in a certain way and one is different. Pick  the odd one out.