Final answer:
The correct answer is 'His', which is the possessive adjective in the sentence showing that the hat belongs to the person indicated by 'his'.
Step-by-step explanation:
The possessive adjective in the sentence 'His hat is newer than hers' is 'His'. A possessive adjective is a word that shows ownership or belonging and modifies a noun. In this sentence, 'His' is used to indicate that the hat belongs to the person represented by 'his'. The correct answer to the question is option D, 'His'. In contrast, a possessive pronoun, like 'hers' in the sentence, is used in place of a noun that has already been mentioned and to which ownership or belonging has been established.
In terms of apostrophes, when creating possessive nouns, we usually add 's to the singular form of the word to show possession, such as 'the owner's insurance' or 'the waitress's coat'.