Form an adjective from the given noun:
rust
(a)rustive
(b)rustful
(c)rustous
(d)rustic

Hint: An adjective is a word that expresses an attribute of something. It is the word class that qualifies nouns. For example- beautiful, smart, delicious.

Complete answer: In the given question, we have to find out which of the options includes the correct adjective form of the given word ‘rust’ which is a noun.
Let us thus analyze the options given to us in this question:
(a)'rustive'- It consists of the suffix ‘ive’ at the end. Therefore, option (a) is incorrect as the word ‘rustive’ does not exist.
(b)‘rustful’- It consists of the suffix ‘ful’ at the end. Therefore, option (b) is incorrect as the word ‘rustful’. does not exist.
(c)‘rustous’- It consists of the suffix ‘ous’ at the end. Therefore, option (c) is incorrect as the word ‘rustous’ does not exist.
(d)‘rustic'-It consists of the suffix ‘ic’ at the end. Therefore, option (d) is correct as the word ‘rustic’ is an adjective which means ‘awkwardly simple and provincial’.

Note: In this question, it will be helpful for the student to recall the concept of nouns. A noun is a content word that can be used to refer to a person, place, thing, quality, or action. It is the word class that can serve as the subject or object of a verb, the object of a preposition, or in apposition. For example- king, person, rusty.