Which one of the following words shouldn't be capitalized? A, Abilene B, Red C, king. D, Cattle

The only words that should be capitalized in a sentence are the first word and proper nouns, which are specific people, places, or things. (Ex. Europe, McDonalds). The only word that should be capitalized is Abilene, because it is a specific city. Red, king, and cattle are all common nouns and should not be capitalized unless they are the first word of a sentence.