When will Walmart CEO Doug McMillon retire from his

Three of the following four are like in a certain way and one is different. Pick the odd one out.

Find the odd one that does not belong to that group.

Four number triads have been given, out of which three are alike in some manner and one is different. Select the number triad that is different.

Select the word which does not belong to the same group from the given alternatives.

Select the option in which the numbers are not related in the same way as are the number of the following set.

(9, 18, 81)

Four letter-clusters have been given out of which three are alike in some manner and one is different. Select the letter-cluster that is different. 

Four number pairs have been given, out of which three are alike in some manner and one is different. Select the one that is different. 

Four words have been given, out of which three are alike in some manner and one is different. Select the odd word.

Four letter-clusters have been given out of which four are alike in some manner and one is different. Select the one that is different.