Plzzz the most common rule for forming plural nouns is
a. adding -es to the word.
b. changing the y to i and adding -es.
c. adding -s to the word.
d. dropping the last letter and adding -ies.

The correct option is C. Plural nouns are formed in many ways, but the most common way of forming plural nouns is by adding the letter 's' to the singular form of the noun. For instance, the plural of these nouns: ball, door, mat, cat and dog can be formed simply by adding letter 's' to the singular forms of these nouns.

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