Nouns are words that name people, things, places,
animals, etc.
The plural form of the noun 'child' is formed by adding '-ren' to it.
Option D: 'Children' is the plural form of the noun 'child'. Hence option D is correct.
Option A: 'Childs' is not the correct plural form of the noun. It should be formed using 'ren'. Hence A is wrong.
Option B: 'Children' is already a plural noun and there's no need to add an 's' to it. Hence this option is incorrect.
Option C: 'Child' is a singular noun that names a young human being. It's not a plural noun and hence C is wrong.