Directions: Pick the odd one out.

History, key, valley, storey, monkey

Correct. The four words - key, valley, storey, and monkey – follow the same rule while forming the plurals (by adding –s to the singular noun). (Rule: If the singular noun ends with -y and the -y has a vowel before it, simply add -s to form the plural.) Thus, the plural forms of these words are – keys, valleys, storeys and monkeys. The word ‘history’ is the odd one here since it ends with –y but has a consonant before the -y. In such a case, the plural is formed by changing –y into –ies (histories).