Use the comparative form in the following sentence:-
My aunt is ____________ (young) than my uncle.
A. As young as
B. More young
C. Younger
D. The younger

Hint:There are three grades for adjectives that equate one thing to another. Positive, comparative and superlative are the three classes of adjectives. The superlative degree (smartest) of the same adjective is used in this expression to compare a person against two or more persons.

Complete answer:
When a distinction is made between two nouns, the expression is of the comparative degree, and when one noun (aunt) is better in terms of consistency than the other (uncle), the quality adjective is 'young' here. The 'young" comparative form is' younger than '. Option C is right, because we need to write the term in the comparative form. Option A is wrong since the clause in it belongs to the positive degree. Option B is wrong because where the adjectives have more than two syllables, the comparative 'more' is used to form comparative adjectives, and 'young' only has one syllable. Option D is wrong since, although the article is a superlative, the term is in the comparative sense.

Hence the correct answer is option C.

Note:Comparison is a characteristic of the grammar or syntax of some languages whereby adjectives and adverbs are inflected to indicate the relative degree of the property they represent expressed by the word or phrase that they modify or describe. The comparative construction, in languages that have it, communicates consistency, quantity, or degree relative to some other comparator.