What type of bridges are commonly used in mountain

Select the odd letters from the given alternatives?

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

Find the odd one out.

In the following question select the odd word from the given alternatives.

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

Find out the odd word/letters/number/number pair from the given alternatives.

Find the odd number from the given alternatives.

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 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.